diff --git a/app/modules/wifi.c b/app/modules/wifi.c
index d2b2d2e5..e9d67d0e 100644
--- a/app/modules/wifi.c
+++ b/app/modules/wifi.c
@@ -328,8 +328,8 @@ static int wifi_station_config( lua_State* L )
   if (sl>32 || ssid == NULL)
     return luaL_error( L, "ssid:<32" );
   const char *password = luaL_checklstring( L, 2, &pl );
-  if (pl<8 || pl>64 || password == NULL)
-    return luaL_error( L, "pwd:8~64" );
+  if (pl!=0 && (pl<8 || pl>64) || password == NULL)
+    return luaL_error( L, "pwd:0,8~64" );
 
   c_memset(sta_conf.ssid, 0, 32);
   c_memset(sta_conf.password, 0, 64);