diff --git a/frameworks/innerkitsimpl/common/src/pixel_map.cpp b/frameworks/innerkitsimpl/common/src/pixel_map.cpp
index 40a021c359c7bbc37032da358adc175b77dddaee..354f0ec09db0bda32011a4e091f8b67634f434ac 100644
--- a/frameworks/innerkitsimpl/common/src/pixel_map.cpp
+++ b/frameworks/innerkitsimpl/common/src/pixel_map.cpp
@@ -807,7 +807,7 @@ void PixelMap::UpdatePixelsAlpha(const AlphaType &alphaType, const PixelFormat &
             alphaIndex = 0;
         }
         if (alphaIndex != -1) {
-            uint8_t pixelBytes = dstPixelMap.GetPixelBytes();
+            uint32_t pixelBytes = static_cast<uint32_t>(dstPixelMap.GetPixelBytes());
             int32_t bufferSize = dstPixelMap.GetByteCount();
             if (bufferSize <= 0) {
                 IMAGE_LOGE("UpdatePixelsAlpha invalid byte count: %{public}d", bufferSize);