diff --git a/cmd/rockusb.c b/cmd/rockusb.c
index 804adb05ab..aa7400ad90 100644
--- a/cmd/rockusb.c
+++ b/cmd/rockusb.c
@@ -154,6 +154,11 @@ static int do_rkusb(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[])
 	devtype = argv[2];
 	devnum	= argv[3];
 
+	if (!strcmp(devtype, "mmc") && !strcmp(devnum, "1")) {
+		pr_err("Forbid to flash mmc 1(sdcard)\n");
+		return CMD_RET_FAILURE;
+	}
+
 	g_rkusb = &rkusb;
 	rc = rkusb_init(devtype, devnum);
 	if (rc < 0)