diff --git a/hutool-core/src/main/java/cn/hutool/core/io/FileTypeUtil.java b/hutool-core/src/main/java/cn/hutool/core/io/FileTypeUtil.java
index cc2a83883dac5277cb1e38338f655af0168bf49d..5e29a0bdb45c4b7853c0601b8e464ccc48264762 100644
--- a/hutool-core/src/main/java/cn/hutool/core/io/FileTypeUtil.java
+++ b/hutool-core/src/main/java/cn/hutool/core/io/FileTypeUtil.java
@@ -53,6 +53,9 @@ public class FileTypeUtil {
 	 * @return 文件类型，未找到为{@code null}
 	 */
 	public static String getType(String fileStreamHexHead) {
+		if (StrUtil.isBlank(fileStreamHexHead)) {
+			return "";
+		}
 		if (MapUtil.isNotEmpty(FILE_TYPE_MAP)) {
 			for (final Entry<String, String> fileTypeEntry : FILE_TYPE_MAP.entrySet()) {
 				if (StrUtil.startWithIgnoreCase(fileStreamHexHead, fileTypeEntry.getKey())) {