diff --git a/services/delivery-platform-api/src/main/java/cn/craftlabs/platform/api/contracts/ContractController.java b/services/delivery-platform-api/src/main/java/cn/craftlabs/platform/api/contracts/ContractController.java
index 43e5636..b18338e 100644
--- a/services/delivery-platform-api/src/main/java/cn/craftlabs/platform/api/contracts/ContractController.java
+++ b/services/delivery-platform-api/src/main/java/cn/craftlabs/platform/api/contracts/ContractController.java
@@ -16,10 +16,13 @@ import jakarta.validation.Valid;
 import jakarta.validation.constraints.Max;
 import jakarta.validation.constraints.Min;
 import java.io.File;
+import java.io.IOException;
 import java.time.OffsetDateTime;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 import org.springframework.http.HttpStatus;
+import org.springframework.http.MediaType;
 import org.springframework.http.ResponseEntity;
 import org.springframework.validation.annotation.Validated;
 import org.springframework.web.bind.annotation.DeleteMapping;
@@ -34,6 +37,7 @@ import org.springframework.web.bind.annotation.RequestParam;
 import org.springframework.web.bind.annotation.ResponseStatus;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.multipart.MultipartFile;
+import org.springframework.web.server.ResponseStatusException;
 
 @RestController
 @RequestMapping("/api/v1/contracts")
@@ -50,6 +54,16 @@ public class ContractController {
         this.contractStatusTransitionService = contractStatusTransitionService;
     }
 
+    private static final long MAX_FILE_SIZE = 50 * 1024 * 1024; // 50MB
+    private static final Set<String> ALLOWED_CONTENT_TYPES = Set.of(
+        MediaType.APPLICATION_PDF_VALUE,
+        "image/jpeg", "image/png", "image/tiff",
+        "application/msword",
+        "application/vnd.openxmlformats-officedocument.wordprocessingml.document",
+        "application/vnd.ms-excel",
+        "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"
+    );
+
     @GetMapping
     public PageResponse<ContractResponse> list(
             @RequestParam(value = "page", defaultValue = "0") @Min(0) int page,
@@ -113,28 +127,44 @@ public class ContractController {
     public ResponseEntity<Map<String, Object>> uploadAttachment(
             @PathVariable Long id,
             @RequestParam("file") MultipartFile file) {
-        try {
-            String uploadDir = System.getProperty("user.dir") + "/uploads/contracts/" + id + "/";
-            File dir = new File(uploadDir);
-            if (!dir.exists()) dir.mkdirs();
-
-            String fileName = System.currentTimeMillis() + "_" + file.getOriginalFilename();
-            File dest = new File(uploadDir + fileName);
-            file.transferTo(dest);
-
-            PlatformContractAttachment attachment = new PlatformContractAttachment();
-            attachment.setContractId(id);
-            attachment.setFileName(file.getOriginalFilename());
-            attachment.setFilePath(dest.getAbsolutePath());
-            attachment.setFileSize(file.getSize());
-            attachment.setContentType(file.getContentType());
-            attachment.setCreatedAt(OffsetDateTime.now());
-            attachmentMapper.insert(attachment);
-
-            return ResponseEntity.ok(Map.of("id", attachment.getId(), "fileName", attachment.getFileName()));
-        } catch (Exception e) {
-            return ResponseEntity.status(500).body(Map.of("error", e.getMessage()));
+        if (file.isEmpty()) {
+            throw new ResponseStatusException(HttpStatus.BAD_REQUEST, "上传文件为空");
         }
+        if (file.getSize() > MAX_FILE_SIZE) {
+            throw new ResponseStatusException(HttpStatus.BAD_REQUEST, "文件大小超过限制（最大 50MB）");
+        }
+        String contentType = file.getContentType();
+        if (contentType == null || !ALLOWED_CONTENT_TYPES.contains(contentType)) {
+            throw new ResponseStatusException(HttpStatus.BAD_REQUEST,
+                "不支持的文件类型: " + (contentType != null ? contentType : "未知"));
+        }
+
+        String uploadDir = System.getProperty("user.dir") + "/uploads/contracts/" + id + "/";
+        File dir = new File(uploadDir);
+        if (!dir.exists()) dir.mkdirs();
+
+        String originalName = file.getOriginalFilename();
+        String ext = originalName != null && originalName.contains(".")
+            ? originalName.substring(originalName.lastIndexOf('.'))
+            : "";
+        String storedName = java.util.UUID.randomUUID().toString() + ext;
+        File dest = new File(uploadDir + storedName);
+        try {
+            file.transferTo(dest);
+        } catch (IOException e) {
+            throw new ResponseStatusException(HttpStatus.INTERNAL_SERVER_ERROR, "文件存储失败");
+        }
+
+        PlatformContractAttachment attachment = new PlatformContractAttachment();
+        attachment.setContractId(id);
+        attachment.setFileName(originalName);
+        attachment.setFilePath(dest.getAbsolutePath());
+        attachment.setFileSize(file.getSize());
+        attachment.setContentType(contentType);
+        attachment.setCreatedAt(OffsetDateTime.now());
+        attachmentMapper.insert(attachment);
+
+        return ResponseEntity.ok(Map.of("id", attachment.getId(), "fileName", attachment.getFileName()));
     }
 
     @GetMapping("/{id}/attachments")
diff --git a/services/delivery-platform-api/src/main/java/cn/craftlabs/platform/api/license/LicenseController.java b/services/delivery-platform-api/src/main/java/cn/craftlabs/platform/api/license/LicenseController.java
index 78faa8c..1d06cc2 100644
--- a/services/delivery-platform-api/src/main/java/cn/craftlabs/platform/api/license/LicenseController.java
+++ b/services/delivery-platform-api/src/main/java/cn/craftlabs/platform/api/license/LicenseController.java
@@ -22,7 +22,7 @@ public class LicenseController {
         try {
             return ResponseEntity.ok(licenseService.create(request));
         } catch (Exception e) {
-            return ResponseEntity.internalServerError().body(Map.of("error", e.getMessage()));
+            throw new RuntimeException(e);
         }
     }