diff --git a/src/reactivity/reactive.ts b/src/reactivity/reactive.ts
index 7599ab68..d08b7c5b 100644
--- a/src/reactivity/reactive.ts
+++ b/src/reactivity/reactive.ts
@@ -94,14 +94,14 @@ export function defineAccessControl(target: AnyObject, key: any, val?: any) {
     set: function setterHandler(newVal: any) {
       if (getter && !setter) return
 
-      const value = getter ? getter.call(target) : val
       // If the key is equal to RefKey, skip the unwrap logic
       // If and only if "value" is ref and "newVal" is not a ref,
       // the assignment should be proxied to "value" ref.
-      if (key !== RefKey && isRef(value) && !isRef(newVal)) {
-        value.value = newVal
+      if (key !== RefKey && isRef(val) && !isRef(newVal)) {
+        val.value = newVal
       } else if (setter) {
         setter.call(target, newVal)
+        val = newVal
       } else {
         val = newVal
       }
diff --git a/test/v3/runtime-core/apiWatch.spec.ts b/test/v3/runtime-core/apiWatch.spec.ts
index 6fde5b24..d1f440a1 100644
--- a/test/v3/runtime-core/apiWatch.spec.ts
+++ b/test/v3/runtime-core/apiWatch.spec.ts
@@ -532,6 +532,28 @@ describe('api: watch', () => {
     expect(data2.value).toMatchObject([1])
   })
 
+  // #498
+  it('watchEffect should not lead to infinite loop when accessing', async () => {
+    let dummy = 0
+
+    const state = reactive({
+      data: [],
+      watchVar: 123,
+    })
+
+    watchEffect(() => {
+      // accessing
+      state.watchVar
+      // setting
+      state.data = []
+      dummy += 1
+    })
+
+    expect(dummy).toBe(1)
+    await nextTick()
+    expect(dummy).toBe(1)
+  })
+
   it('watching deep ref', async () => {
     const count = ref(0)
     const double = computed(() => count.value * 2)