diff --git a/components/dfs/src/dfs_file.c b/components/dfs/src/dfs_file.c
index eb9ca3a167d0dc23126ac6c379a31e4de5cce3a7..2be7552d89d2aa736093760a4685f257d8bc2eb8 100644
--- a/components/dfs/src/dfs_file.c
+++ b/components/dfs/src/dfs_file.c
@@ -834,7 +834,7 @@ FINSH_FUNCTION_EXPORT(rm, remove files or directories);
 void cat(const char *filename)
 {
     struct dfs_fd fd;
-    uint32_t length = 0;
+    int length = 0;
     char buffer[81];
 
     fd_init(&fd);