diff --git a/yudao-module-llm/yudao-module-llm-biz/src/main/java/cn/iocoder/yudao/module/llm/service/http/RagHttpService.java b/yudao-module-llm/yudao-module-llm-biz/src/main/java/cn/iocoder/yudao/module/llm/service/http/RagHttpService.java
index e500727ad..9a98b2a42 100644
--- a/yudao-module-llm/yudao-module-llm-biz/src/main/java/cn/iocoder/yudao/module/llm/service/http/RagHttpService.java
+++ b/yudao-module-llm/yudao-module-llm-biz/src/main/java/cn/iocoder/yudao/module/llm/service/http/RagHttpService.java
@@ -131,6 +131,7 @@ public class RagHttpService {
 
                                 // 发送上传请求
                                 HttpResponse<String> uploadResponse = Unirest.post(ragUploadReqVO.getUrl())
+                                        .header("Content-Type", "multipart/form-data")
                                         .field("file_id", ragUploadReqVO.getFileId())
                                         .field("file", new ByteArrayInputStream(utf8Bytes), ragUploadReqVO.getFileName())
                                         .asString();