diff --git a/chunk.go b/chunk.go
index 09f7e41..509aa26 100644
--- a/chunk.go
+++ b/chunk.go
@@ -164,6 +164,7 @@ func Chunk(ctx context.Context,
 	cb GraphBuildCallback,
 	ef *ExtraFile,
 	randomRenameSourceFile bool,
+	randomSelectFile bool,
 ) error {
 	var cumuSize int64 = 0
 	graphSliceCount := 0
@@ -185,8 +186,16 @@ func Chunk(ctx context.Context,
 		log.Warn("Empty folder or file!")
 		return nil
 	}
+	var allFiles []Finfo
 	files := GetFileListAsync(args)
 	for item := range files {
+		allFiles = append(allFiles, item)
+	}
+	log.Infof("total files: %d", len(allFiles))
+
+	Shuffle(allFiles)
+
+	for _, item := range allFiles {
 		item := item
 		if randomRenameSourceFile {
 			item = tryRenameFileName([]Finfo{item})[0]
diff --git a/cmd/graphsplit/main.go b/cmd/graphsplit/main.go
index c228365..8352a73 100644
--- a/cmd/graphsplit/main.go
+++ b/cmd/graphsplit/main.go
@@ -95,6 +95,11 @@ var chunkCmd = &cli.Command{
 			Name:  "loop",
 			Usage: "loop chunking",
 		},
+		&cli.BoolFlag{
+			Name:  "random-select-file",
+			Usage: "random select file to chunk",
+			Value: true,
+		},
 	},
 	ArgsUsage: "<input path>",
 	Action: func(c *cli.Context) error {
@@ -104,6 +109,7 @@ var chunkCmd = &cli.Command{
 		carDir := c.String("car-dir")
 		graphName := c.String("graph-name")
 		randomRenameSourceFile := c.Bool("random-rename-source-file")
+		randomSelectFile := c.Bool("random-select-file")
 		if !graphsplit.ExistDir(carDir) {
 			return fmt.Errorf("the path of car-dir does not exist")
 		}
@@ -144,7 +150,7 @@ var chunkCmd = &cli.Command{
 		if sliceSize+int(extraFileSliceSize) > 32*graphsplit.Gib {
 			return fmt.Errorf("slice size %d + extra file slice size %d exceeds 32 GiB", sliceSize, extraFileSliceSize)
 		}
-		log.Infof("extra file slice size: %d, random rename source file: %v", extraFileSliceSize, randomRenameSourceFile)
+		log.Infof("extra file slice size: %d, random rename source file: %v, random select file: %v", extraFileSliceSize, randomRenameSourceFile, randomSelectFile)
 		rf, err := graphsplit.NewRealFile(strings.TrimSuffix(cfg.ExtraFilePath, "/"), int64(extraFileSliceSize), int64(sliceSize), randomRenameSourceFile)
 		if err != nil {
 			return err
@@ -164,11 +170,11 @@ var chunkCmd = &cli.Command{
 		fmt.Println("loop: ", loop)
 		if !loop {
 			fmt.Println("chunking once...")
-			return graphsplit.Chunk(ctx, int64(sliceSize), parentPath, targetPath, carDir, graphName, int(parallel), cb, rf, randomRenameSourceFile)
+			return graphsplit.Chunk(ctx, int64(sliceSize), parentPath, targetPath, carDir, graphName, int(parallel), cb, rf, randomRenameSourceFile, randomSelectFile)
 		}
 		fmt.Println("loop chunking...")
 		for {
-			err = graphsplit.Chunk(ctx, int64(sliceSize), parentPath, targetPath, carDir, graphName, int(parallel), cb, rf, randomRenameSourceFile)
+			err = graphsplit.Chunk(ctx, int64(sliceSize), parentPath, targetPath, carDir, graphName, int(parallel), cb, rf, randomRenameSourceFile, randomSelectFile)
 			if err != nil {
 				return fmt.Errorf("failed to chunk: %v", err)
 			}
diff --git a/extra_file.go b/extra_file.go
index 8cd2a5b..b0db8b3 100644
--- a/extra_file.go
+++ b/extra_file.go
@@ -39,7 +39,7 @@ func (rf *ExtraFile) walk(randomRenameSourceFile bool) {
 	if randomRenameSourceFile {
 		rf.files = tryRenameFileName(rf.files)
 	}
-
+	Shuffle(rf.files)
 }
 
 func (rf *ExtraFile) getFiles() []Finfo {
diff --git a/utils.go b/utils.go
index 687073e..d9f608e 100644
--- a/utils.go
+++ b/utils.go
@@ -646,3 +646,15 @@ func RandomLetters() string {
 
 	return string(selected)
 }
+
+// Shuffle 使用泛型和自定义种子随机打乱任意类型的切片
+func Shuffle[T any](arr []T) {
+	s := rand.NewSource(time.Now().UnixNano())
+	r := rand.New(s)
+
+	// Fisher-Yates 洗牌算法
+	for i := len(arr) - 1; i > 0; i-- {
+		j := r.Intn(i + 1)
+		arr[i], arr[j] = arr[j], arr[i]
+	}
+}