diff --git a/src/index.ts b/src/index.ts
index df9de7c3a8836f1da3791593b18eadb328d014af..d6dfb2ff4afe0f9ae2d7a533e1ad411e6e1cbc9d 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -200,11 +200,13 @@ const layer = {
 };
 
 // 全局安装
-const install = (app: App, options: InstallOptions): void => {
+const install = (app: App, options?: InstallOptions): void => {
   layer._context = app._context;
-  app.provide(zIndexKey, options.zIndex)
   app.component(LayLayer.name, LayLayer);
   app.config.globalProperties.$layer = layer;
+  if(options){
+    app.provide(zIndexKey, options.zIndex);
+  }
 };
 
 export { layer, LayLayer };