diff --git a/packages/form/src/Form.vue b/packages/form/src/Form.vue
index a8f89eee..a750a753 100644
--- a/packages/form/src/Form.vue
+++ b/packages/form/src/Form.vue
@@ -92,14 +92,45 @@ const fields = new Map<string, any>();
 
 const requestFuc = getConfig('request') as Function;
 
+/**
+ * formState 实现说明：
+ *
+ * 1. 与 props 直接对应的字段（config / initValues / lastValues / isCompare / parentValues /
+ *    keyProp / popperClass）使用「访问器（getter）」定义，每次读取都会回到 `props.xxx`
+ *    取最新值，不存在「props 变了但 formState 还没同步过来」的中间态。
+ *
+ * 2. `values` / `lastValuesProcessed` 是 ref，Vue 的 `reactive` 会自动解包，因此每次
+ *    访问 `formState.values` / `formState.lastValuesProcessed` 也都是当前 ref 值。
+ *
+ * 3. `extendState` 注入的字段在下方的 `watchEffect` 中合并到 `formState`：
+ *    - data 描述符（普通字段）通过 `formState[key] = value` 写入，走 reactive proxy 的
+ *      set，触发依赖通知；`extendState` 同步段读到的响应式数据变化时会自动重跑，
+ *      把最新值刷进 formState。
+ *    - accessor 描述符（`{ get stage() { return ... } }`）按原样写入，调用方可以控制
+ *      读时求值，每次读取都会重新执行 getter。
+ */
 const formState: FormState = reactive<FormState>({
-  keyProp: props.keyProp,
-  popperClass: props.popperClass,
-  config: props.config,
-  initValues: props.initValues,
-  isCompare: props.isCompare,
-  lastValues: props.lastValues,
-  parentValues: props.parentValues,
+  get keyProp() {
+    return props.keyProp;
+  },
+  get popperClass() {
+    return props.popperClass;
+  },
+  get config() {
+    return props.config;
+  },
+  get initValues() {
+    return props.initValues;
+  },
+  get isCompare() {
+    return props.isCompare;
+  },
+  get lastValues() {
+    return props.lastValues;
+  },
+  get parentValues() {
+    return props.parentValues;
+  },
   values,
   lastValuesProcessed,
   $emit: emit as (_event: string, ..._args: any[]) => void,
@@ -119,20 +150,52 @@ const formState: FormState = reactive<FormState>({
   },
 });
 
-watchEffect(async () => {
-  formState.initValues = props.initValues;
-  formState.lastValues = props.lastValues;
-  formState.isCompare = props.isCompare;
-  formState.config = props.config;
-  formState.keyProp = props.keyProp;
-  formState.popperClass = props.popperClass;
-  formState.parentValues = props.parentValues;
+/**
+ * `extendState` 的同步段（直到第一个 `await` 之前）所访问的任何响应式数据，
+ * 都会被 `watchEffect` 自动跟踪。这样可以兼容历史用法 ——
+ *
+ *   extendState: (formState) => ({
+ *     username: store.username,   // 同步读 store，会被跟踪
+ *     env: store.env,
+ *   })
+ *
+ * 当 `store.username` 变化时，整个 effect 重跑，新值会被刷进 `formState`。
+ *
+ * prop 派生字段（initValues / config / ...）已经在上方用 getter 定义，
+ * 这里不再重复同步；因此 `props.initValues` 这类高频变化也不会再触发
+ * `extendState` 重跑（旧版的性能问题修复点）。
+ *
+ * 实现细节：
+ * - data 描述符：通过 `formState[key] = value` 走 reactive proxy 的 set，
+ *   触发依赖通知；与旧版「逐项赋值」语义完全等价。
+ * - accessor 描述符（`{ get stage() {...} }`）按原样写入 formState，调用方
+ *   可以自行控制读时求值；强制 `configurable: true` 以便下一次重跑可再 define。
+ */
+watchEffect(async (onCleanup) => {
+  const { extendState } = props;
+  if (typeof extendState !== 'function') return;
 
-  if (typeof props.extendState === 'function') {
-    const state = (await props.extendState(formState)) || {};
-    Object.entries(state).forEach(([key, value]) => {
-      formState[key] = value;
-    });
+  let stale = false;
+  onCleanup(() => {
+    stale = true;
+  });
+
+  let state: Record<string, any> = {};
+  try {
+    state = (await extendState(formState)) || {};
+  } catch (e) {
+    console.error('[MForm] extendState failed:', e);
+    return;
+  }
+  if (stale) return;
+
+  for (const [key, descriptor] of Object.entries(Object.getOwnPropertyDescriptors(state))) {
+    if ('value' in descriptor) {
+      (formState as any)[key] = (state as any)[key];
+    } else {
+      descriptor.configurable = true;
+      Object.defineProperty(formState, key, descriptor);
+    }
   }
 });
 
diff --git a/packages/form/tests/unit/Form.extra.spec.ts b/packages/form/tests/unit/Form.extra.spec.ts
new file mode 100644
index 00000000..b20223e9
--- /dev/null
+++ b/packages/form/tests/unit/Form.extra.spec.ts
@@ -0,0 +1,515 @@
+/*
+ * Tencent is pleased to support the open source community by making TMagicEditor available.
+ *
+ * Copyright (C) 2025 Tencent.  All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+import { afterEach, beforeEach, describe, expect, test, vi } from 'vitest';
+import { nextTick, ref } from 'vue';
+import MagicForm, { MForm } from '@form/index';
+import { mount } from '@vue/test-utils';
+import ElementPlus from 'element-plus';
+
+const mountForm = (props: Record<string, any> = {}, options: Record<string, any> = {}) =>
+  mount(MForm, {
+    global: {
+      plugins: [ElementPlus as any, MagicForm as any],
+    },
+    props: {
+      initValues: {},
+      config: [],
+      ...props,
+    },
+    ...options,
+  });
+
+describe('Form.vue —— 默认 props', () => {
+  test('未传任何 props 时使用默认值，渲染不报错', async () => {
+    const wrapper = mountForm();
+    await nextTick();
+
+    expect(wrapper.find('.m-form').exists()).toBe(true);
+    expect(wrapper.vm.values).toEqual({});
+    expect(wrapper.vm.changeRecords).toEqual([]);
+  });
+
+  test('height/labelWidth 透传到样式与子表单', async () => {
+    const wrapper = mountForm({ height: '300px', labelWidth: '120px' });
+    await nextTick();
+
+    const formEl = wrapper.find('.m-form').element as HTMLElement;
+    expect(formEl.getAttribute('style') || '').toContain('height: 300px');
+  });
+});
+
+describe('Form.vue —— formState getter 行为', () => {
+  test('formState 的 keyProp / popperClass / config / initValues / isCompare / lastValues / parentValues 始终回读最新 props', async () => {
+    const wrapper = mountForm({
+      keyProp: 'id',
+      popperClass: 'pop-a',
+      isCompare: false,
+      initValues: { a: 1 },
+      lastValues: { a: 0 },
+      parentValues: { x: 1 },
+      config: [{ text: 'a', name: 'a' }],
+    });
+    await nextTick();
+
+    const fs1: any = wrapper.vm.formState;
+    expect(fs1.keyProp).toBe('id');
+    expect(fs1.popperClass).toBe('pop-a');
+    expect(fs1.isCompare).toBe(false);
+    expect(fs1.initValues).toEqual({ a: 1 });
+    expect(fs1.lastValues).toEqual({ a: 0 });
+    expect(fs1.parentValues).toEqual({ x: 1 });
+    expect(Array.isArray(fs1.config)).toBe(true);
+
+    // 修改 props，formState 上的 getter 应直接反映新值（无中间态）
+    await wrapper.setProps({
+      keyProp: 'uuid',
+      popperClass: 'pop-b',
+      isCompare: true,
+      parentValues: { x: 2 },
+    });
+
+    const fs2: any = wrapper.vm.formState;
+    expect(fs2.keyProp).toBe('uuid');
+    expect(fs2.popperClass).toBe('pop-b');
+    expect(fs2.isCompare).toBe(true);
+    expect(fs2.parentValues).toEqual({ x: 2 });
+  });
+
+  test('values / lastValuesProcessed 在 formState 上自动解包为 ref 当前值', async () => {
+    const wrapper = mountForm({
+      isCompare: true,
+      initValues: { a: '1' },
+      lastValues: { a: '2' },
+      config: [{ text: 'a', type: 'text', name: 'a' }],
+    });
+    await nextTick();
+    await nextTick();
+    await nextTick();
+
+    expect((wrapper.vm.formState as any).values).toEqual({ a: '1' });
+    expect((wrapper.vm.formState as any).lastValuesProcessed).toEqual({ a: '2' });
+  });
+});
+
+describe('Form.vue —— extendState', () => {
+  test('extendState 抛错时被 catch，不影响表单渲染', async () => {
+    const errorSpy = vi.spyOn(console, 'error').mockImplementation(() => {});
+
+    const extendState = vi.fn(async () => {
+      throw new Error('boom');
+    });
+
+    const wrapper = mountForm({
+      extendState,
+      config: [{ text: 'text', name: 'text', type: 'text' }],
+    });
+
+    await nextTick();
+    await nextTick();
+
+    expect(extendState).toHaveBeenCalled();
+    expect(errorSpy).toHaveBeenCalled();
+    expect(wrapper.find('.m-form').exists()).toBe(true);
+
+    errorSpy.mockRestore();
+  });
+
+  test('extendState 返回的普通字段被合并到 formState', async () => {
+    const wrapper = mountForm({
+      extendState: async () => ({ extra: 'hello', count: 42 }),
+    });
+
+    await nextTick();
+    await nextTick();
+    await nextTick();
+
+    expect((wrapper.vm.formState as any).extra).toBe('hello');
+    expect((wrapper.vm.formState as any).count).toBe(42);
+  });
+
+  test('extendState 返回的 accessor 描述符按原样定义并支持读时求值', async () => {
+    let counter = 0;
+
+    const wrapper = mountForm({
+      extendState: () =>
+        Object.defineProperties(
+          {},
+          {
+            stage: {
+              enumerable: true,
+              get() {
+                counter += 1;
+                return `stage-${counter}`;
+              },
+            },
+          },
+        ),
+    });
+
+    await nextTick();
+    await nextTick();
+    await nextTick();
+
+    const v1 = (wrapper.vm.formState as any).stage;
+    const v2 = (wrapper.vm.formState as any).stage;
+
+    expect(v1).not.toEqual(v2);
+    expect(v1).toMatch(/^stage-/);
+    expect(v2).toMatch(/^stage-/);
+  });
+
+  test('extendState 同步段读到的响应式数据变化时会重跑', async () => {
+    const username = ref('alice');
+    const calls: string[] = [];
+
+    const wrapper = mountForm({
+      // 同步读取 ref，会被 watchEffect 跟踪
+      extendState: (_state: any) => {
+        calls.push(username.value);
+        return { username: username.value };
+      },
+    });
+
+    await nextTick();
+    await nextTick();
+    expect((wrapper.vm.formState as any).username).toBe('alice');
+
+    username.value = 'bob';
+    await nextTick();
+    await nextTick();
+    await nextTick();
+
+    expect((wrapper.vm.formState as any).username).toBe('bob');
+    // 至少跑了两次（初始 + 响应变化）
+    expect(calls.length).toBeGreaterThanOrEqual(2);
+  });
+
+  test('未传 extendState 时 watchEffect 早退，不抛错', async () => {
+    const wrapper = mountForm({});
+    await nextTick();
+    expect(wrapper.find('.m-form').exists()).toBe(true);
+  });
+});
+
+describe('Form.vue —— resetForm / changeRecords', () => {
+  test('resetForm 会清空 changeRecords', async () => {
+    const wrapper = mountForm({
+      config: [{ text: 'text', type: 'text', name: 'text' }],
+    });
+    await nextTick();
+
+    wrapper.find('input').setValue('hi');
+    await nextTick();
+
+    expect(wrapper.vm.changeRecords.length).toBeGreaterThan(0);
+
+    wrapper.vm.resetForm();
+    await nextTick();
+
+    expect(wrapper.vm.changeRecords).toEqual([]);
+  });
+});
+
+describe('Form.vue —— submitForm 实例方法', () => {
+  test('校验通过返回 cloneDeep 后的 values', async () => {
+    const wrapper = mountForm({
+      config: [{ text: 'text', type: 'text', name: 'text' }],
+      initValues: { text: 'hi' },
+    });
+    await nextTick();
+
+    const result = await wrapper.vm.submitForm();
+    expect(result).toEqual({ text: 'hi' });
+    // 默认 cloneDeep，应该不是同一引用
+    expect(result).not.toBe(wrapper.vm.values);
+  });
+
+  test('native=true 直接返回原 values 引用', async () => {
+    const wrapper = mountForm({
+      config: [{ text: 'text', type: 'text', name: 'text' }],
+      initValues: { text: 'hi' },
+    });
+    await nextTick();
+
+    const result = await wrapper.vm.submitForm(true);
+    expect(result).toBe(wrapper.vm.values);
+  });
+
+  test('校验失败时 emit error 并抛出汇总后的错误（错误信息中包含字段 text）', async () => {
+    const wrapper = mountForm({
+      config: [
+        {
+          text: '名称',
+          type: 'text',
+          name: 'name',
+        },
+      ],
+      initValues: { name: '' },
+    });
+    await nextTick();
+
+    // 替换 useTemplateRef 暴露的 validate（写入 $.exposed 才能影响内部 setup 中的 tMagicFormRef.value）
+    const tmForm = wrapper.findComponent({ name: 'TMForm' });
+    expect(tmForm.exists()).toBe(true);
+
+    const invalidFields = {
+      name: [{ field: 'name', message: '必填' }],
+    };
+    const { exposed } = (tmForm.vm as any).$;
+    exposed.validate = vi.fn().mockRejectedValue(invalidFields);
+
+    let caught: Error | null = null;
+    try {
+      await wrapper.vm.submitForm();
+    } catch (e: any) {
+      caught = e;
+    }
+
+    expect(caught).toBeInstanceOf(Error);
+    expect(caught!.message).toContain('名称');
+    expect(caught!.message).toContain('必填');
+    expect(wrapper.emitted('error')).toBeTruthy();
+    expect(wrapper.emitted('error')![0][0]).toEqual(invalidFields);
+  });
+
+  test('校验返回非 true（tdesign 风格）时也走错误分支', async () => {
+    const wrapper = mountForm({
+      config: [{ text: '账号', type: 'text', name: 'account' }],
+      initValues: { account: '' },
+    });
+    await nextTick();
+
+    const tmForm = wrapper.findComponent({ name: 'TMForm' });
+    const invalidFields = {
+      account: [{ field: 'account', message: '不能为空' }],
+    };
+    const { exposed } = (tmForm.vm as any).$;
+    exposed.validate = vi.fn().mockResolvedValue(invalidFields);
+
+    let caught: Error | null = null;
+    try {
+      await wrapper.vm.submitForm();
+    } catch (e: any) {
+      caught = e;
+    }
+
+    expect(caught).toBeInstanceOf(Error);
+    expect(caught!.message).toContain('账号');
+    expect(caught!.message).toContain('不能为空');
+  });
+
+  test('校验失败但 invalidFields 中字段无对应 text 时回退使用 field/prop 名', async () => {
+    const wrapper = mountForm({
+      config: [{ text: 'a', type: 'text', name: 'a' }],
+      initValues: { a: '' },
+    });
+    await nextTick();
+
+    const tmForm = wrapper.findComponent({ name: 'TMForm' });
+    const { exposed } = (tmForm.vm as any).$;
+    exposed.validate = vi.fn().mockRejectedValue({
+      unknown: [{ field: '', message: '出错' }],
+    });
+
+    let caught: Error | null = null;
+    try {
+      await wrapper.vm.submitForm();
+    } catch (e: any) {
+      caught = e;
+    }
+
+    expect(caught).toBeInstanceOf(Error);
+    // field 为空 -> 用 prop（unknown）
+    expect(caught!.message).toContain('unknown');
+    expect(caught!.message).toContain('出错');
+  });
+});
+
+describe('Form.vue —— getTextByName', () => {
+  let wrapper: ReturnType<typeof mountForm>;
+
+  beforeEach(async () => {
+    wrapper = mountForm({
+      config: [
+        { text: '名称', type: 'text', name: 'name' },
+        {
+          name: 'object',
+          items: [
+            { text: '内层名称', type: 'text', name: 'inner' },
+            {
+              name: 'nested',
+              items: [{ text: '深层', type: 'text', name: 'deep' }],
+            },
+          ],
+        },
+        // 无 name 的容器，items 应能继续被搜索
+        {
+          items: [{ text: '无名容器内字段', type: 'text', name: 'plain' }],
+        },
+        // text 非字符串
+        { text: { foo: 'bar' } as any, type: 'text', name: 'nonString' },
+      ],
+    });
+    await nextTick();
+  });
+
+  afterEach(() => {
+    wrapper.unmount();
+  });
+
+  test('单层名匹配', () => {
+    expect(wrapper.vm.getTextByName('name')).toBe('名称');
+  });
+
+  test('点分隔多层路径匹配', () => {
+    expect(wrapper.vm.getTextByName('object.inner')).toBe('内层名称');
+    expect(wrapper.vm.getTextByName('object.nested.deep')).toBe('深层');
+  });
+
+  test('无 name 容器的 items 也能被搜索到', () => {
+    expect(wrapper.vm.getTextByName('plain')).toBe('无名容器内字段');
+  });
+
+  test('找不到时返回 undefined', () => {
+    expect(wrapper.vm.getTextByName('not.exist')).toBeUndefined();
+    expect(wrapper.vm.getTextByName('object.unknown')).toBeUndefined();
+  });
+
+  test('text 非字符串时返回 undefined', () => {
+    expect(wrapper.vm.getTextByName('nonString')).toBeUndefined();
+  });
+
+  test('参数非法时返回 undefined', () => {
+    expect(wrapper.vm.getTextByName('')).toBeUndefined();
+    // @ts-expect-error 故意传非数组
+    expect(wrapper.vm.getTextByName('name', null)).toBeUndefined();
+  });
+});
+
+describe('Form.vue —— preventSubmitDefault', () => {
+  test('preventSubmitDefault=true 时 submit 事件 preventDefault 被调用', async () => {
+    const wrapper = mountForm({
+      config: [{ text: 'text', type: 'text', name: 'text' }],
+      preventSubmitDefault: true,
+    });
+    await nextTick();
+
+    const formEl = wrapper.find('.m-form').element as HTMLFormElement;
+    const evt = new Event('submit', { cancelable: true, bubbles: true });
+    const spy = vi.spyOn(evt, 'preventDefault');
+    formEl.dispatchEvent(evt);
+
+    expect(spy).toHaveBeenCalled();
+  });
+
+  test('preventSubmitDefault=false（默认）时不调用 preventDefault', async () => {
+    const wrapper = mountForm({
+      config: [{ text: 'text', type: 'text', name: 'text' }],
+    });
+    await nextTick();
+
+    const formEl = wrapper.find('.m-form').element as HTMLFormElement;
+    const evt = new Event('submit', { cancelable: true, bubbles: true });
+    const spy = vi.spyOn(evt, 'preventDefault');
+    formEl.dispatchEvent(evt);
+
+    expect(spy).not.toHaveBeenCalled();
+  });
+});
+
+describe('Form.vue —— isCompare 模式', () => {
+  test('isCompare=true 时 lastValuesProcessed 会被初始化', async () => {
+    const wrapper = mountForm({
+      isCompare: true,
+      config: [{ text: 'text', type: 'text', name: 'text' }],
+      initValues: { text: 'a' },
+      lastValues: { text: 'b' },
+    });
+
+    await nextTick();
+    await nextTick();
+    await nextTick();
+
+    expect(wrapper.vm.values.text).toBe('a');
+    expect(wrapper.vm.lastValuesProcessed.text).toBe('b');
+    expect(wrapper.vm.initialized).toBe(true);
+  });
+
+  test('isCompare=false 时 lastValuesProcessed 不会被填充', async () => {
+    const wrapper = mountForm({
+      isCompare: false,
+      config: [{ text: 'text', type: 'text', name: 'text' }],
+      initValues: { text: 'a' },
+      lastValues: { text: 'b' },
+    });
+
+    await nextTick();
+    await nextTick();
+    await nextTick();
+
+    expect(wrapper.vm.values.text).toBe('a');
+    expect(wrapper.vm.lastValuesProcessed).toEqual({});
+    expect(wrapper.vm.initialized).toBe(true);
+  });
+});
+
+describe('Form.vue —— config 变化', () => {
+  test('config 引用变化会重新初始化（initialized 短暂置 false 后回 true）', async () => {
+    const wrapper = mountForm({
+      config: [{ text: 'a', type: 'text', name: 'a' }],
+      initValues: { a: '1' },
+    });
+    await nextTick();
+    await nextTick();
+
+    expect(wrapper.vm.initialized).toBe(true);
+
+    await wrapper.setProps({
+      config: [{ text: 'b', type: 'text', name: 'b' }],
+      initValues: { b: '2' },
+    });
+
+    // 第一次 microtask 后还在重建
+    await nextTick();
+    await nextTick();
+    await nextTick();
+
+    expect(wrapper.vm.initialized).toBe(true);
+    expect(wrapper.vm.values).toHaveProperty('b');
+  });
+
+  test('config 变化会清空 changeRecords', async () => {
+    const wrapper = mountForm({
+      config: [{ text: 'a', type: 'text', name: 'a' }],
+    });
+    await nextTick();
+
+    wrapper.find('input').setValue('xx');
+    await nextTick();
+    expect(wrapper.vm.changeRecords.length).toBeGreaterThan(0);
+
+    await wrapper.setProps({
+      config: [{ text: 'b', type: 'text', name: 'b' }],
+      initValues: {},
+    });
+    await nextTick();
+    await nextTick();
+
+    expect(wrapper.vm.changeRecords).toEqual([]);
+  });
+});