diff --git a/src/apis/watch.ts b/src/apis/watch.ts
index 4e1724a4..19df3e24 100644
--- a/src/apis/watch.ts
+++ b/src/apis/watch.ts
@@ -83,7 +83,7 @@ function getWatcherOption(options?: Partial<WatchOptions>): WatchOptions {
     ...{
       immediate: false,
       deep: false,
-      flush: 'post',
+      flush: 'pre',
     },
     ...options,
   }
@@ -94,7 +94,7 @@ function getWatchEffectOption(options?: Partial<WatchOptions>): WatchOptions {
     ...{
       immediate: true,
       deep: false,
-      flush: 'post',
+      flush: 'pre',
     },
     ...options,
   }
diff --git a/test/apis/watch.spec.js b/test/apis/watch.spec.js
index c480f1b2..33f5b626 100644
--- a/test/apis/watch.spec.js
+++ b/test/apis/watch.spec.js
@@ -178,7 +178,7 @@ describe('api/watch', () => {
             spy(newVal, oldVal)
             rerenderedText = vm.$el.textContent
           },
-          { lazy: true }
+          { lazy: true, flush: 'post' }
         )
         return {
           a,
@@ -210,7 +210,7 @@ describe('api/watch', () => {
               rerenderedText = vm.$el.textContent
             }
           },
-          { immediate: true }
+          { immediate: true, flush: 'post' }
         )
         return {
           a,