diff --git a/ruoyi-common/ruoyi-common-core/src/main/java/org/ruoyi/common/core/utils/file/ContentTypeUtil.java b/ruoyi-common/ruoyi-common-core/src/main/java/org/ruoyi/common/core/utils/file/ContentTypeUtil.java
new file mode 100644
index 00000000..59677502
--- /dev/null
+++ b/ruoyi-common/ruoyi-common-core/src/main/java/org/ruoyi/common/core/utils/file/ContentTypeUtil.java
@@ -0,0 +1,61 @@
+package org.ruoyi.common.core.utils.file;
+
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * @Author: xiaoen
+ * @Description: Content-Type 映射工具
+ * @Date: Created in 18:50 2026/3/17
+ */
+public class ContentTypeUtil {
+
+    private static final Map<String, String> CONTENT_TYPE_MAP = new HashMap<>();
+
+    static {
+        // 文本文件
+        CONTENT_TYPE_MAP.put(".txt", "text/plain; charset=UTF-8");
+        CONTENT_TYPE_MAP.put(".html", "text/html; charset=UTF-8");
+        CONTENT_TYPE_MAP.put(".htm", "text/html; charset=UTF-8");
+        CONTENT_TYPE_MAP.put(".css", "text/css; charset=UTF-8");
+        CONTENT_TYPE_MAP.put(".js", "application/javascript; charset=UTF-8");
+        CONTENT_TYPE_MAP.put(".json", "application/json; charset=UTF-8");
+        CONTENT_TYPE_MAP.put(".xml", "application/xml; charset=UTF-8");
+        CONTENT_TYPE_MAP.put(".csv", "text/csv; charset=UTF-8");
+
+        // 图片文件
+        CONTENT_TYPE_MAP.put(".jpg", "image/jpeg");
+        CONTENT_TYPE_MAP.put(".jpeg", "image/jpeg");
+        CONTENT_TYPE_MAP.put(".png", "image/png");
+        CONTENT_TYPE_MAP.put(".gif", "image/gif");
+        CONTENT_TYPE_MAP.put(".bmp", "image/bmp");
+        CONTENT_TYPE_MAP.put(".webp", "image/webp");
+        CONTENT_TYPE_MAP.put(".svg", "image/svg+xml");
+
+        // 应用文件
+        CONTENT_TYPE_MAP.put(".pdf", "application/pdf");
+        CONTENT_TYPE_MAP.put(".doc", "application/msword");
+        CONTENT_TYPE_MAP.put(".docx", "application/vnd.openxmlformats-officedocument.wordprocessingml.document");
+        CONTENT_TYPE_MAP.put(".xls", "application/vnd.ms-excel");
+        CONTENT_TYPE_MAP.put(".xlsx", "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet");
+        CONTENT_TYPE_MAP.put(".ppt", "application/vnd.ms-powerpoint");
+        CONTENT_TYPE_MAP.put(".pptx", "application/vnd.openxmlformats-officedocument.presentationml.presentation");
+
+        // 其他
+        CONTENT_TYPE_MAP.put(".mp3", "audio/mpeg");
+        CONTENT_TYPE_MAP.put(".mp4", "video/mp4");
+        CONTENT_TYPE_MAP.put(".zip", "application/zip");
+        CONTENT_TYPE_MAP.put(".rar", "application/x-rar-compressed");
+    }
+
+    /**
+     * 根据后缀返回对应的 content-type
+     * @param suffix
+     * @param defaultContentType
+     * @return
+     */
+    public static String getContentType(String suffix, String defaultContentType) {
+        String contentType = CONTENT_TYPE_MAP.get(suffix.toLowerCase());
+        return contentType != null ? contentType : defaultContentType;
+    }
+}
diff --git a/ruoyi-modules/ruoyi-system/src/main/java/org/ruoyi/system/service/impl/SysOssServiceImpl.java b/ruoyi-modules/ruoyi-system/src/main/java/org/ruoyi/system/service/impl/SysOssServiceImpl.java
index 8ca967ea..61accdb8 100644
--- a/ruoyi-modules/ruoyi-system/src/main/java/org/ruoyi/system/service/impl/SysOssServiceImpl.java
+++ b/ruoyi-modules/ruoyi-system/src/main/java/org/ruoyi/system/service/impl/SysOssServiceImpl.java
@@ -17,6 +17,7 @@ import org.ruoyi.common.core.utils.MapstructUtils;
 import org.ruoyi.common.core.utils.SpringUtils;
 import org.ruoyi.common.core.utils.StreamUtils;
 import org.ruoyi.common.core.utils.StringUtils;
+import org.ruoyi.common.core.utils.file.ContentTypeUtil;
 import org.ruoyi.common.core.utils.file.FileUtils;
 import org.ruoyi.common.json.utils.JsonUtils;
 import org.ruoyi.common.mybatis.core.page.PageQuery;
@@ -218,7 +219,7 @@ public class SysOssServiceImpl implements ISysOssService, OssService {
         OssClient storage = OssFactory.instance();
         UploadResult uploadResult;
         try {
-            uploadResult = storage.uploadSuffix(file.getBytes(), suffix, file.getContentType());
+            uploadResult = storage.uploadSuffix(file.getBytes(), suffix, ContentTypeUtil.getContentType(suffix, file.getContentType()));
         } catch (IOException e) {
             throw new ServiceException(e.getMessage());
         }