diff --git a/tests/st/__init__.py b/tests/st/__init__.py
index e69de29bb2d1d6434b8b29ae775ad8c2e48c5391..bec7616c824437dbf46b7a1e432e1026f7562504 100644
--- a/tests/st/__init__.py
+++ b/tests/st/__init__.py
@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: Apache-2.0
+from tests.st.python.utils.env_var_manager import EnvVarManager
+
+env_manager = EnvVarManager()
+env_manager.setup_mindformers_environment()
diff --git a/tests/st/python/cases_parallel/multilora_inference.py b/tests/st/python/cases_parallel/multilora_inference.py
index 0a1e3776b970776308bb8cdb25867ea92404eb6f..57d362a71f223e6f4bc617ae7e1e8695755e32a8 100644
--- a/tests/st/python/cases_parallel/multilora_inference.py
+++ b/tests/st/python/cases_parallel/multilora_inference.py
@@ -24,7 +24,6 @@ from unittest.mock import patch
 import os
 
 from tests.st.python.utils.cases_parallel import cleanup_subprocesses
-from tests.st.python.utils.env_var_manager import EnvVarManager
 
 import vllm_mindspore  # noqa: F401
 from typing import Optional
@@ -34,11 +33,10 @@ from vllm.lora.request import LoRARequest
 
 
 def teardown_function():
+    """pytest calls the function after case function completed."""
     cleanup_subprocesses()
 
 
-env_manager = EnvVarManager()
-env_manager.setup_mindformers_environment()
 # def env
 env_vars = {
     "ASCEND_CUSTOM_PATH": os.path.expandvars("$ASCEND_HOME_PATH/../"),
diff --git a/tests/st/python/cases_parallel/shm_broadcast.py b/tests/st/python/cases_parallel/shm_broadcast.py
index c82688c244703ea13026e4fc15602aa2351684fd..03f88f1372936f379cff0f701fc0bb51912a230d 100644
--- a/tests/st/python/cases_parallel/shm_broadcast.py
+++ b/tests/st/python/cases_parallel/shm_broadcast.py
@@ -38,17 +38,13 @@ from vllm.utils import get_ip, get_open_port, get_distributed_init_method
 
 from tests.st.python.test_ds_online import env_vars
 from tests.st.python.utils.cases_parallel import cleanup_subprocesses
-from tests.st.python.utils.env_var_manager import EnvVarManager
 
 
 def teardown_function():
+    """pytest calls the function after case function completed."""
     cleanup_subprocesses()
 
 
-env_manager = EnvVarManager()
-env_manager.setup_mindformers_environment()
-
-
 def get_arrays(n: int, seed: int = 0) -> list[np.ndarray]:
     np.random.seed(seed)
     sizes = np.random.randint(1, 10_000, n)
diff --git a/tests/st/python/cases_parallel/vllm_deepseek_bf16_part.py b/tests/st/python/cases_parallel/vllm_deepseek_bf16_part.py
index d113591690a8c0254b13cd6e64c581299db1873c..524282593c690af4823748ec372640874b489ecd 100644
--- a/tests/st/python/cases_parallel/vllm_deepseek_bf16_part.py
+++ b/tests/st/python/cases_parallel/vllm_deepseek_bf16_part.py
@@ -19,15 +19,13 @@ from unittest.mock import patch
 
 import os
 from tests.st.python.utils.cases_parallel import cleanup_subprocesses
-from tests.st.python.utils.env_var_manager import EnvVarManager
 
 
 def teardown_function():
+    """pytest calls the function after case function completed."""
     cleanup_subprocesses()
 
 
-env_manager = EnvVarManager()
-env_manager.setup_mindformers_environment()
 # def env
 env_vars = {
     "ASCEND_CUSTOM_PATH": os.path.expandvars("$ASCEND_HOME_PATH/../"),
diff --git a/tests/st/python/cases_parallel/vllm_deepseek_bf16_part_v1.py b/tests/st/python/cases_parallel/vllm_deepseek_bf16_part_v1.py
index 649f1b7a0a3e394b177606f13a273eb20e797d67..d83d08953f0d9f2ab1b158727079350dcac46319 100644
--- a/tests/st/python/cases_parallel/vllm_deepseek_bf16_part_v1.py
+++ b/tests/st/python/cases_parallel/vllm_deepseek_bf16_part_v1.py
@@ -19,15 +19,13 @@ from unittest.mock import patch
 
 import os
 from tests.st.python.utils.cases_parallel import cleanup_subprocesses
-from tests.st.python.utils.env_var_manager import EnvVarManager
 
 
 def teardown_function():
+    """pytest calls the function after case function completed."""
     cleanup_subprocesses()
 
 
-env_manager = EnvVarManager()
-env_manager.setup_mindformers_environment()
 # def env
 env_vars = {
     "ASCEND_CUSTOM_PATH": os.path.expandvars("$ASCEND_HOME_PATH/../"),
diff --git a/tests/st/python/cases_parallel/vllm_deepseek_osl.py b/tests/st/python/cases_parallel/vllm_deepseek_osl.py
index 68c54fd79d8c1b1e15831ec79a590cd7cf0e28d4..132f06dcccde9c30bdbe99226fa853bbe0aaa686 100644
--- a/tests/st/python/cases_parallel/vllm_deepseek_osl.py
+++ b/tests/st/python/cases_parallel/vllm_deepseek_osl.py
@@ -25,15 +25,13 @@ from unittest.mock import patch
 
 import os
 from tests.st.python.utils.cases_parallel import cleanup_subprocesses
-from tests.st.python.utils.env_var_manager import EnvVarManager
 
 
 def teardown_function():
+    """pytest calls the function after case function completed."""
     cleanup_subprocesses()
 
 
-env_manager = EnvVarManager()
-env_manager.setup_mindformers_environment()
 # def env
 env_vars = {
     "ASCEND_CUSTOM_PATH": os.path.expandvars("$ASCEND_HOME_PATH/../"),
diff --git a/tests/st/python/cases_parallel/vllm_deepseek_part.py b/tests/st/python/cases_parallel/vllm_deepseek_part.py
index 8ed5ce6f62851ac9a8609b7bf5cea46b6025ce4a..c34fac3e6ca3f702b209cfbca0fee0c5662ebc32 100644
--- a/tests/st/python/cases_parallel/vllm_deepseek_part.py
+++ b/tests/st/python/cases_parallel/vllm_deepseek_part.py
@@ -19,15 +19,13 @@ from unittest.mock import patch
 
 import os
 from tests.st.python.utils.cases_parallel import cleanup_subprocesses
-from tests.st.python.utils.env_var_manager import EnvVarManager
 
 
 def teardown_function():
+    """pytest calls the function after case function completed."""
     cleanup_subprocesses()
 
 
-env_manager = EnvVarManager()
-env_manager.setup_mindformers_environment()
 # def env
 env_vars = {
     "ASCEND_CUSTOM_PATH": os.path.expandvars("$ASCEND_HOME_PATH/../"),
diff --git a/tests/st/python/cases_parallel/vllm_deepseek_part_v1.py b/tests/st/python/cases_parallel/vllm_deepseek_part_v1.py
index 06cacc3556a31c11a809e442e1f288e6512a509f..f7f7fbc978906c082b93a5910b30427338ba54fb 100644
--- a/tests/st/python/cases_parallel/vllm_deepseek_part_v1.py
+++ b/tests/st/python/cases_parallel/vllm_deepseek_part_v1.py
@@ -20,15 +20,13 @@ from unittest.mock import patch
 import os
 
 from tests.st.python.utils.cases_parallel import cleanup_subprocesses
-from tests.st.python.utils.env_var_manager import EnvVarManager
 
 
 def teardown_function():
+    """pytest calls the function after case function completed."""
     cleanup_subprocesses()
 
 
-env_manager = EnvVarManager()
-env_manager.setup_mindformers_environment()
 # def env
 env_vars = {
     "ASCEND_CUSTOM_PATH": os.path.expandvars("$ASCEND_HOME_PATH/../"),
diff --git a/tests/st/python/cases_parallel/vllm_deepseek_smoothquant.py b/tests/st/python/cases_parallel/vllm_deepseek_smoothquant.py
index 748b43373edd7760a76ad5cfb44ee1cb11b9aaa1..6289af06594af60ab8222837b1bf46707142b967 100644
--- a/tests/st/python/cases_parallel/vllm_deepseek_smoothquant.py
+++ b/tests/st/python/cases_parallel/vllm_deepseek_smoothquant.py
@@ -23,15 +23,13 @@ from unittest.mock import patch
 import os
 
 from tests.st.python.utils.cases_parallel import cleanup_subprocesses
-from tests.st.python.utils.env_var_manager import EnvVarManager
 
 
 def teardown_function():
+    """pytest calls the function after case function completed."""
     cleanup_subprocesses()
 
 
-env_manager = EnvVarManager()
-env_manager.setup_mindformers_environment()
 # def env
 env_vars = {
     "ASCEND_CUSTOM_PATH": os.path.expandvars("$ASCEND_HOME_PATH/../"),
diff --git a/tests/st/python/cases_parallel/vllm_deepseek_smoothquant_mss.py b/tests/st/python/cases_parallel/vllm_deepseek_smoothquant_mss.py
index 3733060910bd671e29109add2da1c05b83b07661..be545974da109a716661de41d2dc71414cffed65 100644
--- a/tests/st/python/cases_parallel/vllm_deepseek_smoothquant_mss.py
+++ b/tests/st/python/cases_parallel/vllm_deepseek_smoothquant_mss.py
@@ -23,15 +23,13 @@ from unittest.mock import patch
 import os
 
 from tests.st.python.utils.cases_parallel import cleanup_subprocesses
-from tests.st.python.utils.env_var_manager import EnvVarManager
 
 
 def teardown_function():
+    """pytest calls the function after case function completed."""
     cleanup_subprocesses()
 
 
-env_manager = EnvVarManager()
-env_manager.setup_mindformers_environment()
 # def env
 env_vars = {
     "ASCEND_CUSTOM_PATH": os.path.expandvars("$ASCEND_HOME_PATH/../"),
diff --git a/tests/st/python/cases_parallel/vllm_llama3.py b/tests/st/python/cases_parallel/vllm_llama3.py
index 8355cbd81f3337dcabc2937101eea9210a876a7d..ab01e639c83e51860a0d8d88db9e7e4a3a628012 100644
--- a/tests/st/python/cases_parallel/vllm_llama3.py
+++ b/tests/st/python/cases_parallel/vllm_llama3.py
@@ -22,13 +22,16 @@ from unittest.mock import patch
 import os
 
 from tests.st.python.utils.cases_parallel import cleanup_subprocesses
-from tests.st.python.utils.env_var_manager import EnvVarManager
+
+
+def teardown_function():
+    """pytest calls the function after case function completed."""
+    cleanup_subprocesses()
+
 
 import vllm_mindspore
 from vllm import LLM, SamplingParams
 
-env_manager = EnvVarManager()
-env_manager.setup_mindformers_environment()
 # def env
 env_vars = {
     "ASCEND_CUSTOM_PATH": os.path.expandvars("$ASCEND_HOME_PATH/../"),
diff --git a/tests/st/python/cases_parallel/vllm_mf_qwen3_8b.py b/tests/st/python/cases_parallel/vllm_mf_qwen3_8b.py
index 7324d1c15b5e6dc300bf5576fe5069f81491e3c9..1f5ce1fe4026f42373f39551ab70008b22a9b4a9 100644
--- a/tests/st/python/cases_parallel/vllm_mf_qwen3_8b.py
+++ b/tests/st/python/cases_parallel/vllm_mf_qwen3_8b.py
@@ -20,15 +20,13 @@ from unittest.mock import patch
 import os
 
 from tests.st.python.utils.cases_parallel import cleanup_subprocesses
-from tests.st.python.utils.env_var_manager import EnvVarManager
 
 
 def teardown_function():
+    """pytest calls the function after case function completed."""
     cleanup_subprocesses()
 
 
-env_manager = EnvVarManager()
-env_manager.setup_mindformers_environment()
 # def env
 env_vars = {
     "ASCEND_CUSTOM_PATH": os.path.expandvars("$ASCEND_HOME_PATH/../"),
diff --git a/tests/st/python/cases_parallel/vllm_mf_qwen_7b.py b/tests/st/python/cases_parallel/vllm_mf_qwen_7b.py
index 2ee512fda70fee0e5fa09c5407a276a881a515e8..eef712c323082bdaeffba6e8e5e7423f15907195 100644
--- a/tests/st/python/cases_parallel/vllm_mf_qwen_7b.py
+++ b/tests/st/python/cases_parallel/vllm_mf_qwen_7b.py
@@ -20,15 +20,13 @@ from unittest.mock import patch
 import os
 
 from tests.st.python.utils.cases_parallel import cleanup_subprocesses
-from tests.st.python.utils.env_var_manager import EnvVarManager
 
 
 def teardown_function():
+    """pytest calls the function after case function completed."""
     cleanup_subprocesses()
 
 
-env_manager = EnvVarManager()
-env_manager.setup_mindformers_environment()
 # def env
 env_vars = {
     "ASCEND_CUSTOM_PATH": os.path.expandvars("$ASCEND_HOME_PATH/../"),
diff --git a/tests/st/python/cases_parallel/vllm_mf_qwen_7b_chunk_prefill.py b/tests/st/python/cases_parallel/vllm_mf_qwen_7b_chunk_prefill.py
index ffb30ce93e28fac171f914978d95b670a45c02d1..7d4c1531b4463eb0b8d9de56786b3fd13e408058 100644
--- a/tests/st/python/cases_parallel/vllm_mf_qwen_7b_chunk_prefill.py
+++ b/tests/st/python/cases_parallel/vllm_mf_qwen_7b_chunk_prefill.py
@@ -20,15 +20,13 @@ from unittest.mock import patch
 import os
 
 from tests.st.python.utils.cases_parallel import cleanup_subprocesses
-from tests.st.python.utils.env_var_manager import EnvVarManager
 
 
 def teardown_function():
+    """pytest calls the function after case function completed."""
     cleanup_subprocesses()
 
 
-env_manager = EnvVarManager()
-env_manager.setup_mindformers_environment()
 # def env
 env_vars = {
     "ASCEND_CUSTOM_PATH": os.path.expandvars("$ASCEND_HOME_PATH/../"),
diff --git a/tests/st/python/cases_parallel/vllm_mf_qwen_7b_chunk_prefill_v1.py b/tests/st/python/cases_parallel/vllm_mf_qwen_7b_chunk_prefill_v1.py
index 5d80b0a0bfd82f571d54b2d780d0eb4dc02e8ae2..21d81fbf5ea625c029297d50aee81db1ee5affca 100644
--- a/tests/st/python/cases_parallel/vllm_mf_qwen_7b_chunk_prefill_v1.py
+++ b/tests/st/python/cases_parallel/vllm_mf_qwen_7b_chunk_prefill_v1.py
@@ -20,15 +20,13 @@ from unittest.mock import patch
 import os
 
 from tests.st.python.utils.cases_parallel import cleanup_subprocesses
-from tests.st.python.utils.env_var_manager import EnvVarManager
 
 
 def teardown_function():
+    """pytest calls the function after case function completed."""
     cleanup_subprocesses()
 
 
-env_manager = EnvVarManager()
-env_manager.setup_mindformers_environment()
 # def env
 env_vars = {
     "ASCEND_CUSTOM_PATH": os.path.expandvars("$ASCEND_HOME_PATH/../"),
diff --git a/tests/st/python/cases_parallel/vllm_mf_qwen_7b_cp_pc_mss.py b/tests/st/python/cases_parallel/vllm_mf_qwen_7b_cp_pc_mss.py
index 72a7c7aaa70641200bae1d07779c74d4046861e8..37cfe7468f675522baa6091ddfbfcfbc99ba7a9c 100644
--- a/tests/st/python/cases_parallel/vllm_mf_qwen_7b_cp_pc_mss.py
+++ b/tests/st/python/cases_parallel/vllm_mf_qwen_7b_cp_pc_mss.py
@@ -20,15 +20,13 @@ from unittest.mock import patch
 import os
 
 from tests.st.python.utils.cases_parallel import cleanup_subprocesses
-from tests.st.python.utils.env_var_manager import EnvVarManager
 
 
 def teardown_function():
+    """pytest calls the function after case function completed."""
     cleanup_subprocesses()
 
 
-env_manager = EnvVarManager()
-env_manager.setup_mindformers_environment()
 # def env
 env_vars = {
     "ASCEND_CUSTOM_PATH": os.path.expandvars("$ASCEND_HOME_PATH/../"),
diff --git a/tests/st/python/cases_parallel/vllm_mf_qwen_7b_mss.py b/tests/st/python/cases_parallel/vllm_mf_qwen_7b_mss.py
index 30e5a49a5b8b26f789479d6246bf036d6e1b8086..cf65dc3f08888134438d23c9a5c756dcd3b70645 100644
--- a/tests/st/python/cases_parallel/vllm_mf_qwen_7b_mss.py
+++ b/tests/st/python/cases_parallel/vllm_mf_qwen_7b_mss.py
@@ -20,15 +20,13 @@ from unittest.mock import patch
 import os
 
 from tests.st.python.utils.cases_parallel import cleanup_subprocesses
-from tests.st.python.utils.env_var_manager import EnvVarManager
 
 
 def teardown_function():
+    """pytest calls the function after case function completed."""
     cleanup_subprocesses()
 
 
-env_manager = EnvVarManager()
-env_manager.setup_mindformers_environment()
 # def env
 env_vars = {
     "ASCEND_CUSTOM_PATH": os.path.expandvars("$ASCEND_HOME_PATH/../"),
diff --git a/tests/st/python/cases_parallel/vllm_mf_qwen_7b_prefix_caching.py b/tests/st/python/cases_parallel/vllm_mf_qwen_7b_prefix_caching.py
index 8ac1e28cf3336a4adcf1c2db6d9cfbeedc554a21..8a9c54f1e4a028c0aafc4e9aaebc0e6e652d5b74 100644
--- a/tests/st/python/cases_parallel/vllm_mf_qwen_7b_prefix_caching.py
+++ b/tests/st/python/cases_parallel/vllm_mf_qwen_7b_prefix_caching.py
@@ -19,15 +19,13 @@ from unittest.mock import patch
 
 import os
 from tests.st.python.utils.cases_parallel import cleanup_subprocesses
-from tests.st.python.utils.env_var_manager import EnvVarManager
 
 
 def teardown_function():
+    """pytest calls the function after case function completed."""
     cleanup_subprocesses()
 
 
-env_manager = EnvVarManager()
-env_manager.setup_mindformers_environment()
 env_vars = {
     "ASCEND_CUSTOM_PATH": os.path.expandvars("$ASCEND_HOME_PATH/../"),
     "VLLM_MS_MODEL_BACKEND": "MindFormers",
diff --git a/tests/st/python/cases_parallel/vllm_mf_qwen_7b_prefix_caching_v1.py b/tests/st/python/cases_parallel/vllm_mf_qwen_7b_prefix_caching_v1.py
index 6fb0c6084b228f2b8a97f768b05b54c8a86f1925..b2d6c45719ad30b5a0e61472362b735aa8cd19d4 100644
--- a/tests/st/python/cases_parallel/vllm_mf_qwen_7b_prefix_caching_v1.py
+++ b/tests/st/python/cases_parallel/vllm_mf_qwen_7b_prefix_caching_v1.py
@@ -19,15 +19,13 @@ from unittest.mock import patch
 
 import os
 from tests.st.python.utils.cases_parallel import cleanup_subprocesses
-from tests.st.python.utils.env_var_manager import EnvVarManager
 
 
 def teardown_function():
+    """pytest calls the function after case function completed."""
     cleanup_subprocesses()
 
 
-env_manager = EnvVarManager()
-env_manager.setup_mindformers_environment()
 env_vars = {
     "ASCEND_CUSTOM_PATH": os.path.expandvars("$ASCEND_HOME_PATH/../"),
     "VLLM_MS_MODEL_BACKEND": "MindFormers",
diff --git a/tests/st/python/cases_parallel/vllm_mf_qwen_7b_v1.py b/tests/st/python/cases_parallel/vllm_mf_qwen_7b_v1.py
index 70bca2447d61144c1ae8d3042ba69129f447dd0c..3870b4d7329749ee3a410b6d4c72fb4d30062158 100644
--- a/tests/st/python/cases_parallel/vllm_mf_qwen_7b_v1.py
+++ b/tests/st/python/cases_parallel/vllm_mf_qwen_7b_v1.py
@@ -19,15 +19,13 @@ from unittest.mock import patch
 
 import os
 from tests.st.python.utils.cases_parallel import cleanup_subprocesses
-from tests.st.python.utils.env_var_manager import EnvVarManager
 
 
 def teardown_function():
+    """pytest calls the function after case function completed."""
     cleanup_subprocesses()
 
 
-env_manager = EnvVarManager()
-env_manager.setup_mindformers_environment()
 # def env
 env_vars = {
     "ASCEND_CUSTOM_PATH": os.path.expandvars("$ASCEND_HOME_PATH/../"),
diff --git a/tests/st/python/cases_parallel/vllm_mf_telechat2_7b.py b/tests/st/python/cases_parallel/vllm_mf_telechat2_7b.py
index 0a38a51b9e952e00e62decf6043a1efe56f57423..8592728a56169d56e405a2e651ba3ac5c4eae28d 100644
--- a/tests/st/python/cases_parallel/vllm_mf_telechat2_7b.py
+++ b/tests/st/python/cases_parallel/vllm_mf_telechat2_7b.py
@@ -20,15 +20,13 @@ from unittest.mock import patch
 import os
 
 from tests.st.python.utils.cases_parallel import cleanup_subprocesses
-from tests.st.python.utils.env_var_manager import EnvVarManager
 
 
 def teardown_function():
+    """pytest calls the function after case function completed."""
     cleanup_subprocesses()
 
 
-env_manager = EnvVarManager()
-env_manager.setup_mindformers_environment()
 # def env
 env_vars = {
     "ASCEND_CUSTOM_PATH": os.path.expandvars("$ASCEND_HOME_PATH/../"),
diff --git a/tests/st/python/cases_parallel/vllm_qwen2_5_vl_7b_v1.py b/tests/st/python/cases_parallel/vllm_qwen2_5_vl_7b_v1.py
index dc36d54881316ae2c66aae0fc763d8115e86d82b..94a9b7b7f9590db063ed6274c26a8aae7d4d2b15 100644
--- a/tests/st/python/cases_parallel/vllm_qwen2_5_vl_7b_v1.py
+++ b/tests/st/python/cases_parallel/vllm_qwen2_5_vl_7b_v1.py
@@ -24,17 +24,15 @@ import cv2
 import numpy as np
 from PIL import Image
 from tests.st.python.utils.cases_parallel import cleanup_subprocesses
-from tests.st.python.utils.env_var_manager import EnvVarManager
 from tests.st.python.cases_parallel.similarity import compare_distance
 from transformers import AutoProcessor
 
 
 def teardown_function():
+    """pytest calls the function after case function completed."""
     cleanup_subprocesses()
 
 
-env_manager = EnvVarManager()
-env_manager.setup_mindformers_environment()
 # def env
 env_vars = {
     "ASCEND_CUSTOM_PATH": os.path.expandvars("$ASCEND_HOME_PATH/../"),
diff --git a/tests/st/python/cases_parallel/vllm_qwen3.py b/tests/st/python/cases_parallel/vllm_qwen3.py
index f2eb008c1b65a7b3a8a5a260bf8ea25056f1d170..396c824087cc7fe38fe66b41d23d8eac66ced183 100644
--- a/tests/st/python/cases_parallel/vllm_qwen3.py
+++ b/tests/st/python/cases_parallel/vllm_qwen3.py
@@ -22,15 +22,13 @@ from unittest.mock import patch
 import os
 
 from tests.st.python.utils.cases_parallel import cleanup_subprocesses
-from tests.st.python.utils.env_var_manager import EnvVarManager
 
 
 def teardown_function():
+    """pytest calls the function after case function completed."""
     cleanup_subprocesses()
 
 
-env_manager = EnvVarManager()
-env_manager.setup_mindformers_environment()
 # def env
 env_vars = {
     "ASCEND_CUSTOM_PATH": os.path.expandvars("$ASCEND_HOME_PATH/../"),
diff --git a/tests/st/python/cases_parallel/vllm_qwen3_moe.py b/tests/st/python/cases_parallel/vllm_qwen3_moe.py
index ec2d57377a7ba9351b8aa3199fbc440f7b680162..8a1fd6baad3b454df90712ee8d6c9afcbabfc2c8 100644
--- a/tests/st/python/cases_parallel/vllm_qwen3_moe.py
+++ b/tests/st/python/cases_parallel/vllm_qwen3_moe.py
@@ -22,15 +22,13 @@ from unittest.mock import patch
 import os
 
 from tests.st.python.utils.cases_parallel import cleanup_subprocesses
-from tests.st.python.utils.env_var_manager import EnvVarManager
 
 
 def teardown_function():
+    """pytest calls the function after case function completed."""
     cleanup_subprocesses()
 
 
-env_manager = EnvVarManager()
-env_manager.setup_mindformers_environment()
 # def env
 env_vars = {
     "ASCEND_CUSTOM_PATH": os.path.expandvars("$ASCEND_HOME_PATH/../"),
diff --git a/tests/st/python/cases_parallel/vllm_qwen_7b.py b/tests/st/python/cases_parallel/vllm_qwen_7b.py
index 8a6e9301a2f8e06566cbb6ef1bf0c026d64bbc0f..dbe3857fdbc7c0ecf439b33cad5927ef5f9945fb 100644
--- a/tests/st/python/cases_parallel/vllm_qwen_7b.py
+++ b/tests/st/python/cases_parallel/vllm_qwen_7b.py
@@ -19,15 +19,13 @@ from unittest.mock import patch
 
 import os
 from tests.st.python.utils.cases_parallel import cleanup_subprocesses
-from tests.st.python.utils.env_var_manager import EnvVarManager
 
 
 def teardown_function():
+    """pytest calls the function after case function completed."""
     cleanup_subprocesses()
 
 
-env_manager = EnvVarManager()
-env_manager.setup_mindformers_environment()
 # def env
 env_vars = {
     "ASCEND_CUSTOM_PATH": os.path.expandvars("$ASCEND_HOME_PATH/../"),
diff --git a/tests/st/python/cases_parallel/vllm_qwen_7b_v1.py b/tests/st/python/cases_parallel/vllm_qwen_7b_v1.py
index 35c3e0b7002758caabeaf304061c0aa4afb6ffef..81abb1c81326601946528cf0bbdb672855afa7fe 100644
--- a/tests/st/python/cases_parallel/vllm_qwen_7b_v1.py
+++ b/tests/st/python/cases_parallel/vllm_qwen_7b_v1.py
@@ -19,15 +19,13 @@ from unittest.mock import patch
 
 import os
 from tests.st.python.utils.cases_parallel import cleanup_subprocesses
-from tests.st.python.utils.env_var_manager import EnvVarManager
 
 
 def teardown_function():
+    """pytest calls the function after case function completed."""
     cleanup_subprocesses()
 
 
-env_manager = EnvVarManager()
-env_manager.setup_mindformers_environment()
 # def env
 env_vars = {
     "ASCEND_CUSTOM_PATH": os.path.expandvars("$ASCEND_HOME_PATH/../"),
diff --git a/tests/st/python/cases_parallel/vllm_sampling.py b/tests/st/python/cases_parallel/vllm_sampling.py
index d9578d54c7753db8ac82ef3f00be62dc46754360..960cebddd44d8eb1bc011b0eb3ddeb819d082651 100644
--- a/tests/st/python/cases_parallel/vllm_sampling.py
+++ b/tests/st/python/cases_parallel/vllm_sampling.py
@@ -19,15 +19,13 @@ from unittest.mock import patch
 
 import os
 from tests.st.python.utils.cases_parallel import cleanup_subprocesses
-from tests.st.python.utils.env_var_manager import EnvVarManager
 
 
 def teardown_function():
+    """pytest calls the function after case function completed."""
     cleanup_subprocesses()
 
 
-env_manager = EnvVarManager()
-env_manager.setup_mindformers_environment()
 # def env
 env_vars = {
     "ASCEND_CUSTOM_PATH": os.path.expandvars("$ASCEND_HOME_PATH/../"),
diff --git a/tests/st/python/cell/test_attention.py b/tests/st/python/cell/test_attention.py
index 9216757ce039c687c298eb613b391edd2deaf62d..1919e0bc02ad89eb4a9ff56682758b1d03c5c133 100644
--- a/tests/st/python/cell/test_attention.py
+++ b/tests/st/python/cell/test_attention.py
@@ -30,6 +30,13 @@ from vllm_mindspore.model_executor.layers.quantization.attention import (
 from vllm.config import CacheConfig
 from vllm.attention.backends.abstract import AttentionType
 
+from tests.st.python.utils.cases_parallel import cleanup_subprocesses
+
+
+def teardown_function():
+    """pytest calls the function after case function completed."""
+    cleanup_subprocesses()
+
 
 @pytest.fixture(params=[mstype.float16, mstype.bfloat16],
                 ids=["float16", "bfloat16"])
diff --git a/tests/st/python/cell/test_smooth_quant.py b/tests/st/python/cell/test_smooth_quant.py
index 4be2a5f7e5a7cda1cf71684ea460d794a2e597bd..b0c0ec764a106663ced917c57f4163bd01927c7c 100644
--- a/tests/st/python/cell/test_smooth_quant.py
+++ b/tests/st/python/cell/test_smooth_quant.py
@@ -25,6 +25,13 @@ from mindspore.common.initializer import initializer
 from vllm_mindspore.model_executor.layers.quantization.smooth_quant_modelslim \
     import A8W8DYNLinearMethod, A8W8LinearMethod, SmoothQuantModelSlimConfig
 
+from tests.st.python.utils.cases_parallel import cleanup_subprocesses
+
+
+def teardown_function():
+    """pytest calls the function after case function completed."""
+    cleanup_subprocesses()
+
 
 @pytest.fixture(params=[mstype.float16, mstype.bfloat16],
                 ids=["float16", "bfloat16"])
diff --git a/tests/st/python/test_custom_advstepflash.py b/tests/st/python/test_custom_advstepflash.py
index cd779f3192f8dfa1b24892d7f8e32fb4db25f228..91873dea5a895ded8f87ca2b1e285849d548cce9 100644
--- a/tests/st/python/test_custom_advstepflash.py
+++ b/tests/st/python/test_custom_advstepflash.py
@@ -26,6 +26,7 @@ from tests.st.python.utils.cases_parallel import cleanup_subprocesses
 
 
 def teardown_function():
+    """pytest calls the function after case function completed."""
     cleanup_subprocesses()
 
 
diff --git a/tests/st/python/test_deepseekv3_tool_parser.py b/tests/st/python/test_deepseekv3_tool_parser.py
index c641fed558b603f6e202a94175dbd23747866868..8e8b0eed80d19cc2fbb2887b50a158000ba736b7 100644
--- a/tests/st/python/test_deepseekv3_tool_parser.py
+++ b/tests/st/python/test_deepseekv3_tool_parser.py
@@ -31,6 +31,13 @@ from vllm.entrypoints.openai.protocol import (ChatCompletionRequest,
                                               FunctionCall, ToolCall)
 from vllm.entrypoints.openai.tool_parsers import ToolParser, ToolParserManager
 
+from tests.st.python.utils.cases_parallel import cleanup_subprocesses
+
+
+def teardown_function():
+    """pytest calls the function after case function completed."""
+    cleanup_subprocesses()
+
 
 class StreamingToolReconstructor:
 
diff --git a/tests/st/python/test_ds_online.py b/tests/st/python/test_ds_online.py
index ed342ffc3cada9a7b8353d69c0db72b48a02989d..b1c497cb5419dcd7e7c303503dac276e33f24b27 100644
--- a/tests/st/python/test_ds_online.py
+++ b/tests/st/python/test_ds_online.py
@@ -26,10 +26,14 @@ import shlex
 import signal
 import time
 
-from tests.st.python.utils.env_var_manager import EnvVarManager
+from tests.st.python.utils.cases_parallel import cleanup_subprocesses
+
+
+def teardown_function():
+    """pytest calls the function after case function completed."""
+    cleanup_subprocesses()
+
 
-env_manager = EnvVarManager()
-env_manager.setup_mindformers_environment()
 env_vars = {
     "vLLM_MODEL_BACKEND": "MindFormers",
     "MS_ENABLE_LCCL": "off",
diff --git a/tests/st/python/test_mcore_mix_parallel.py b/tests/st/python/test_mcore_mix_parallel.py
index 148f0878612b6a405f9d37d209411a2ce7b816e2..b017f41fea2f95205d62cc9d22bcc1ef9131cdf4 100644
--- a/tests/st/python/test_mcore_mix_parallel.py
+++ b/tests/st/python/test_mcore_mix_parallel.py
@@ -22,15 +22,13 @@ import os
 from multiprocessing import Process, Queue
 
 from tests.st.python.utils.cases_parallel import cleanup_subprocesses
-from tests.st.python.utils.env_var_manager import EnvVarManager
 
 
 def teardown_function():
+    """pytest calls the function after case function completed."""
     cleanup_subprocesses()
 
 
-env_manager = EnvVarManager()
-env_manager.setup_mindformers_environment()
 env_vars = {
     "ASCEND_CUSTOM_PATH": os.path.expandvars("$ASCEND_HOME_PATH/../"),
     "VLLM_MS_MODEL_BACKEND": "MindFormers",
diff --git a/tests/st/python/test_sampler.py b/tests/st/python/test_sampler.py
index 4a6c4795d36252454ba1d209b226363545e23752..aabd6f34764dd830c18667cb843837aae887d619 100644
--- a/tests/st/python/test_sampler.py
+++ b/tests/st/python/test_sampler.py
@@ -45,6 +45,7 @@ from tests.st.python.utils.cases_parallel import cleanup_subprocesses
 
 
 def teardown_function():
+    """pytest calls the function after case function completed."""
     cleanup_subprocesses()
 
 
diff --git a/tests/st/python/test_sampler_v1.py b/tests/st/python/test_sampler_v1.py
index 126629273f4ae1470f7ecf95a9ee8312c32f1623..d696da90a64c74ff2a6a596c973d6751e1628c5d 100644
--- a/tests/st/python/test_sampler_v1.py
+++ b/tests/st/python/test_sampler_v1.py
@@ -37,6 +37,7 @@ from tests.st.python.utils.cases_parallel import cleanup_subprocesses
 
 
 def teardown_function():
+    """pytest calls the function after case function completed."""
     cleanup_subprocesses()