diff --git a/frontend/src/hooks/useSliceUpload.tsx b/frontend/src/hooks/useSliceUpload.tsx
index 6fe76b0..848d9b3 100644
--- a/frontend/src/hooks/useSliceUpload.tsx
+++ b/frontend/src/hooks/useSliceUpload.tsx
@@ -251,18 +251,6 @@ export function useFileSliceUpload(
         const file = files[i];
         console.log(`[useSliceUpload] Processing file ${i + 1}/${files.length}: ${file.name}`);
         
-        // 为每个文件单独调用 preUpload，获取独立的 reqId
-        const { data: reqId } = await preUpload(task.key, {
-          totalFileNum: 1,
-          totalSize: file.size,
-          datasetId: task.key,
-          hasArchive: task.hasArchive,
-          prefix: task.prefix,
-        });
-        
-        console.log(`[useSliceUpload] File ${file.name} preUpload response reqId:`, reqId);
-        reqIds.push(reqId);
-        
         const result = await streamSplitAndUpload(
           file,
           (formData, config) => uploadChunk(task.key, formData, {
@@ -292,10 +280,21 @@ export function useFileSliceUpload(
               },
             };
             updateTaskList(updatedTask);
-          },
+          }, 
           1024 * 1024, // 1MB chunk size
           {
-            reqId,
+            resolveReqId: async ({ totalFileNum, totalSize }) => {
+              const { data: reqId } = await preUpload(task.key, {
+                totalFileNum,
+                totalSize,
+                datasetId: task.key,
+                hasArchive: task.hasArchive,
+                prefix: task.prefix,
+              });
+              console.log(`[useSliceUpload] File ${file.name} preUpload response reqId:`, reqId);
+              reqIds.push(reqId);
+              return reqId;
+            },
             hasArchive: newTask.hasArchive,
             prefix: newTask.prefix,
             signal: newTask.controller.signal,
diff --git a/frontend/src/utils/file.util.ts b/frontend/src/utils/file.util.ts
index 9606ddc..883f3f7 100644
--- a/frontend/src/utils/file.util.ts
+++ b/frontend/src/utils/file.util.ts
@@ -401,7 +401,9 @@ export function readFileAsText(
  * @returns 上传结果统计
  */
 export interface StreamUploadOptions {
-  reqId: number;
+  reqId?: number;
+  resolveReqId?: (params: { totalFileNum: number; totalSize: number }) => Promise<number>;
+  onReqIdResolved?: (reqId: number) => void;
   fileNamePrefix?: string;
   hasArchive?: boolean;
   prefix?: string;
@@ -422,8 +424,16 @@ export async function streamSplitAndUpload(
   chunkSize: number = 1024 * 1024, // 1MB
   options: StreamUploadOptions
 ): Promise<StreamUploadResult> {
-  const { reqId, fileNamePrefix, prefix, signal, maxConcurrency = 3 } = options;
-  
+  const {
+    reqId: initialReqId,
+    resolveReqId,
+    onReqIdResolved,
+    fileNamePrefix,
+    prefix,
+    signal,
+    maxConcurrency = 3,
+  } = options;
+
   const fileSize = file.size;
   let offset = 0;
   let buffer = "";
@@ -441,7 +451,7 @@ export async function streamSplitAndUpload(
   const pendingLines: { line: string; index: number }[] = [];
   let lineIndex = 0;
 
-  // 逐块读取文件并收集行
+  // 逐块读取文件并收集非空行
   while (offset < fileSize) {
     // 检查是否已取消
     if (signal?.aborted) {
@@ -461,11 +471,15 @@ export async function streamSplitAndUpload(
     // 保留最后一行（可能不完整）
     buffer = lines.pop() || "";
     
-    // 收集完整行
+    // 收集完整行（跳过空行）
     for (const line of lines) {
       if (signal?.aborted) {
         throw new Error("Upload cancelled");
       }
+      if (!line.trim()) {
+        skippedEmptyCount++;
+        continue;
+      }
       pendingLines.push({ line, index: lineIndex++ });
     }
     
@@ -479,12 +493,38 @@ export async function streamSplitAndUpload(
   // 处理最后剩余的 buffer（如果文件不以换行符结尾）
   if (buffer.trim()) {
     pendingLines.push({ line: buffer, index: lineIndex++ });
+  } else if (buffer.length > 0) {
+    skippedEmptyCount++;
+  }
+
+  const totalFileNum = pendingLines.length;
+  if (totalFileNum === 0) {
+    return {
+      uploadedCount: 0,
+      totalBytes: fileSize,
+      skippedEmptyCount,
+    };
+  }
+
+  if (signal?.aborted) {
+    throw new Error("Upload cancelled");
+  }
+
+  let resolvedReqId = initialReqId;
+  if (!resolvedReqId) {
+    if (!resolveReqId) {
+      throw new Error("Missing pre-upload request id");
+    }
+    resolvedReqId = await resolveReqId({ totalFileNum, totalSize: fileSize });
+    if (!resolvedReqId) {
+      throw new Error("Failed to resolve pre-upload request id");
+    }
+    onReqIdResolved?.(resolvedReqId);
   }
 
   /**
    * 上传单行内容
-   * fileNo 固定为 1（因为所有行都属于同一个原始文件，只是不同的分片/行）
-   * chunkNo 用于标识是第几行
+   * 每行作为独立文件上传，fileNo 对应行序号，chunkNo 固定为 1
    */
   async function uploadLine(line: string, index: number): Promise<void> {
     // 检查是否已取消
@@ -498,7 +538,8 @@ export async function streamSplitAndUpload(
     }
 
     // 保留原始文件扩展名
-    const newFileName = `${baseName}_${String(index + 1).padStart(6, "0")}${fileExtension}`;
+    const fileIndex = index + 1;
+    const newFileName = `${baseName}_${String(fileIndex).padStart(6, "0")}${fileExtension}`;
     const blob = new Blob([line], { type: "text/plain" });
     const lineFile = new File([blob], newFileName, { type: "text/plain" });
     
@@ -513,11 +554,10 @@ export async function streamSplitAndUpload(
     
     const formData = new FormData();
     formData.append("file", slices[0]);
-    formData.append("reqId", reqId.toString());
-    // 所有行使用相同的 fileNo=1，因为它们属于同一个预上传请求
-    // chunkNo 表示这是第几行数据
-    formData.append("fileNo", "1");
-    formData.append("chunkNo", (index + 1).toString());
+    formData.append("reqId", resolvedReqId.toString());
+    // 每行作为独立文件上传
+    formData.append("fileNo", fileIndex.toString());
+    formData.append("chunkNo", "1");
     formData.append("fileName", newFileName);
     formData.append("fileSize", lineFile.size.toString());
     formData.append("totalChunkNum", "1");