diff --git a/packages/compiler-core/__tests__/transforms/__snapshots__/vMemo.spec.ts.snap b/packages/compiler-core/__tests__/transforms/__snapshots__/vMemo.spec.ts.snap
index 5fc14defb43..b1f750f15d8 100644
--- a/packages/compiler-core/__tests__/transforms/__snapshots__/vMemo.spec.ts.snap
+++ b/packages/compiler-core/__tests__/transforms/__snapshots__/vMemo.spec.ts.snap
@@ -37,7 +37,7 @@ export function render(_ctx, _cache) {
   return (_openBlock(), _createElementBlock("div", null, [
     (_openBlock(true), _createElementBlock(_Fragment, null, _renderList(_ctx.list, ({ x, y }, __, ___, _cached) => {
       const _memo = ([x, y === _ctx.z])
-      if (_cached && _cached.el && _cached.key === x && _isMemoSame(_cached, _memo)) return _cached
+      if (_cached && _cached.el && _cached.key === (x) && _isMemoSame(_cached, _memo)) return _cached
       const _item = (_openBlock(), _createElementBlock("span", { key: x }, "foobar"))
       _item.memo = _memo
       return _item
@@ -53,7 +53,7 @@ export function render(_ctx, _cache) {
   return (_openBlock(), _createElementBlock("div", null, [
     (_openBlock(true), _createElementBlock(_Fragment, null, _renderList(_ctx.list, ({ x, y }, __, ___, _cached) => {
       const _memo = ([x, y === _ctx.z])
-      if (_cached && _cached.el && _cached.key === _ctx.get(x) && _isMemoSame(_cached, _memo)) return _cached
+      if (_cached && _cached.el && _cached.key === (_ctx.get(x)) && _isMemoSame(_cached, _memo)) return _cached
       const _item = (_openBlock(), _createElementBlock("span", {
         key: _ctx.get(x)
       }, "foobar"))
@@ -71,7 +71,7 @@ export function render(_ctx, _cache) {
   return (_openBlock(), _createElementBlock("div", null, [
     (_openBlock(true), _createElementBlock(_Fragment, null, _renderList(_ctx.list, ({ x, y }, __, ___, _cached) => {
       const _memo = ([x, y === _ctx.z])
-      if (_cached && _cached.el && _cached.key === x && _isMemoSame(_cached, _memo)) return _cached
+      if (_cached && _cached.el && _cached.key === (x) && _isMemoSame(_cached, _memo)) return _cached
       const _item = (_openBlock(), _createElementBlock("div", { key: x }, [
         _createElementVNode("span", null, "foobar")
       ]))
@@ -89,7 +89,7 @@ export function render(_ctx, _cache) {
   return (_openBlock(), _createElementBlock("div", null, [
     (_openBlock(true), _createElementBlock(_Fragment, null, _renderList(_ctx.list, ({ x, y }, __, ___, _cached) => {
       const _memo = ([x, y === _ctx.z])
-      if (_cached && _cached.el && _cached.key === _ctx.get(x) && _isMemoSame(_cached, _memo)) return _cached
+      if (_cached && _cached.el && _cached.key === (_ctx.get(x)) && _isMemoSame(_cached, _memo)) return _cached
       const _item = (_openBlock(), _createElementBlock("div", {
         key: _ctx.get(x)
       }, [
diff --git a/packages/compiler-core/__tests__/transforms/vMemo.spec.ts b/packages/compiler-core/__tests__/transforms/vMemo.spec.ts
index ae21bf9fa1d..11db25934a7 100644
--- a/packages/compiler-core/__tests__/transforms/vMemo.spec.ts
+++ b/packages/compiler-core/__tests__/transforms/vMemo.spec.ts
@@ -75,6 +75,16 @@ describe('compiler: v-memo transform', () => {
     ).toMatchSnapshot()
   })
 
+  test('on v-for w/ conditional key expression', () => {
+    const code = compile(
+      `<div v-for="{ x, y } in list" :key="x ? x : y" v-memo="[x, y === z]">
+        <span>foobar</span>
+      </div>`,
+    )
+
+    expect(code).toContain(`_cached.key === (x ? x : y)`)
+  })
+
   test('on template v-for', () => {
     expect(
       compile(
diff --git a/packages/compiler-core/src/transforms/vFor.ts b/packages/compiler-core/src/transforms/vFor.ts
index ebf67d3d7d1..7899fb813d0 100644
--- a/packages/compiler-core/src/transforms/vFor.ts
+++ b/packages/compiler-core/src/transforms/vFor.ts
@@ -225,7 +225,7 @@ export const transformFor: NodeTransform = createStructuralDirectiveTransform(
             createCompoundExpression([`const _memo = (`, memo.exp!, `)`]),
             createCompoundExpression([
               `if (_cached && _cached.el`,
-              ...(keyExp ? [` && _cached.key === `, keyExp] : []),
+              ...(keyExp ? [` && _cached.key === (`, keyExp, `)`] : []),
               ` && ${context.helperString(
                 IS_MEMO_SAME,
               )}(_cached, _memo)) return _cached`,