diff --git a/packages/taro-router/src/init.ts b/packages/taro-router/src/init.ts
index f3e1dd2299e9..4e9b8bc36066 100644
--- a/packages/taro-router/src/init.ts
+++ b/packages/taro-router/src/init.ts
@@ -3,6 +3,7 @@ import { setHistoryMode } from './history'
 import { RouterConfig } from './router'
 
 export function init (config: RouterConfig) {
+  config.router.mode = config.router.mode || 'hash'
   setHistoryMode(config.router.mode, config.router.basename)
   Object.assign(routerConfig, config)
   document.getElementById('app')?.remove()