diff --git a/porting/liteos_a/user/src/unistd/sync.c b/porting/liteos_a/user/src/unistd/sync.c
deleted file mode 100644
index 666aaf7d79ecde2888c414abe0b7702936a4d0c9..0000000000000000000000000000000000000000
--- a/porting/liteos_a/user/src/unistd/sync.c
+++ /dev/null
@@ -1,10 +0,0 @@
-#include <unistd.h>
-#include <unsupported_api.h>
-
-#include "syscall.h"
-
-void sync(void)
-{
-	unsupported_api(__FUNCTION__);
-	__syscall(SYS_sync);
-}