diff --git a/porting/liteos_m/kernel/src/stdio/ftell.c b/porting/liteos_m/kernel/src/stdio/ftell.c
index d15cc665275f1d5eead43a5ac3535afd6ad46d95..8cf4252b545f2441d5f9c8e91dfd071a8aa69a22 100644
--- a/porting/liteos_m/kernel/src/stdio/ftell.c
+++ b/porting/liteos_m/kernel/src/stdio/ftell.c
@@ -4,7 +4,7 @@
 
 off_t __ftello_unlocked(FILE *f)
 {
-	off_t pos = lseek(f->fd, 0,
+	off_t pos = lseek(f->fd, (off_t)0,
 		(f->flags & F_APP) && f->wpos != f->wbase
 		? SEEK_END : SEEK_CUR);
 	if (pos < 0) return pos;