diff --git a/packages/data-source/src/utils.ts b/packages/data-source/src/utils.ts
index 38b41c5e..81887e92 100644
--- a/packages/data-source/src/utils.ts
+++ b/packages/data-source/src/utils.ts
@@ -75,6 +75,45 @@ export const updateNode = (node: MNode, dsl: MApp) => {
   }
 };
 
+/**
+ * 将 source 的字段复制到 target，对象型字段使用惰性深拷贝（首次读取时拷贝并缓存）
+ * @param target 目标对象
+ * @param source 源对象
+ * @param skipKey 需要跳过的字段
+ */
+const assignLazyClone = (target: Record<string, any>, source: Record<string, any> | undefined, skipKey: string) => {
+  if (!source) return;
+
+  for (const key of Object.keys(source)) {
+    if (key === skipKey) continue;
+
+    const value = source[key];
+
+    if (typeof value !== 'object' || value === null) {
+      target[key] = value;
+      continue;
+    }
+
+    let cloned: any;
+    let isCloned = false;
+    Object.defineProperty(target, key, {
+      enumerable: true,
+      configurable: true,
+      get() {
+        if (!isCloned) {
+          cloned = cloneDeep(value);
+          isCloned = true;
+        }
+        return cloned;
+      },
+      set(newValue) {
+        cloned = newValue;
+        isCloned = true;
+      },
+    });
+  }
+};
+
 /**
  * 创建迭代器容器编译的数据上下文
  * @param itemData 迭代数据
@@ -93,24 +132,26 @@ export const createIteratorContentData = (
     [dsId]: {},
   };
 
-  let rawData = cloneDeep(dsData[dsId]);
+  // 沿 fields 路径逐层构造新对象，不修改原始数据。
+  // 路径之外的对象型字段不会预先整体深拷贝（迭代项很多时会导致 O(N²)），而是在首次被读取时才拷贝并缓存，
+  // 这样依然是与数据源隔离的快照（引用每次编译都是新的，保证 vue 组件的 props 能感知到按 path 原地修改的数据）。
+  let rawData: Record<string, any> | undefined = dsData[dsId];
   let obj: Record<string, any> = data[dsId];
 
   fields.forEach((key, index) => {
-    Object.assign(obj, rawData);
+    assignLazyClone(obj, rawData, key);
 
     if (index === fields.length - 1) {
       obj[key] = itemData;
       return;
     }
 
-    if (Array.isArray(rawData[key])) {
-      rawData[key] = {};
-      obj[key] = {};
-    }
+    const next = rawData?.[key];
+    const nextObj: Record<string, any> = {};
+    obj[key] = nextObj;
 
-    rawData = rawData[key];
-    obj = obj[key];
+    rawData = Array.isArray(next) ? undefined : next;
+    obj = nextObj;
   });
 
   return data;
diff --git a/packages/data-source/tests/iterator-reactivity.spec.ts b/packages/data-source/tests/iterator-reactivity.spec.ts
new file mode 100644
index 00000000..b60cf8ae
--- /dev/null
+++ b/packages/data-source/tests/iterator-reactivity.spec.ts
@@ -0,0 +1,156 @@
+import { afterAll, describe, expect, test } from 'vitest';
+import { computed, createApp, defineComponent, h, nextTick, ref } from 'vue';
+
+import TMagicApp, { NodeType } from '@tmagic/core';
+
+import { DataSourceManager } from '@data-source/index';
+
+/**
+ * 模拟 IteratorContainer.vue：
+ * configs 是依赖 props.config 的 computed，内部调用 dataSourceManager.compliedIteratorItems，
+ * 每项渲染一个 Item，Item 把绑定到的“兄弟字段对象”作为 prop 继续传给 Cell。
+ */
+const setup = () => {
+  const dsId = 'ds_iter_reactivity';
+  const app = new TMagicApp({
+    config: {
+      type: NodeType.ROOT,
+      id: 'app_iter_reactivity',
+      items: [],
+      dataSources: [
+        {
+          type: 'base',
+          id: dsId,
+          fields: [
+            {
+              name: 'list',
+              type: 'array',
+              fields: [{ name: 'label' }],
+              defaultValue: [{ label: 'A' }, { label: 'B' }],
+            },
+            { name: 'matrix', type: 'array', fields: [{ name: 'v' }], defaultValue: [{ v: 1 }] },
+          ],
+          methods: [],
+          events: [],
+        },
+      ],
+    },
+  });
+
+  const dsm = new DataSourceManager({ app });
+  const ds = dsm.get(dsId)!;
+
+  const rawMatrix = dsm.data[dsId].matrix;
+
+  const templateNodes = [
+    {
+      id: 'iter_reactivity_node',
+      type: 'text',
+      text: '${ds_iter_reactivity.list.label}',
+      // 绑定整个数据源，编译结果是迭代上下文（matrix 是迭代路径之外的兄弟字段）
+      cell: { isBindDataSource: true, dataSourceId: dsId },
+    },
+  ] as any[];
+
+  const renderCount = { cell: 0, item: 0 };
+
+  const cellComp = defineComponent({
+    props: { matrix: { type: Array, required: true } },
+    setup(props) {
+      return () => {
+        renderCount.cell += 1;
+        return h('i', { class: 'cell' }, String((props.matrix[0] as any).v));
+      };
+    },
+  });
+
+  const itemComp = defineComponent({
+    props: { config: { type: Object, required: true } },
+    setup(props) {
+      return () => {
+        renderCount.item += 1;
+        const node = (props.config as any).items[0];
+        return h('div', { class: 'item' }, [h('b', node.text), h(cellComp, { matrix: node.cell.matrix })]);
+      };
+    },
+  });
+
+  // 与 IteratorContainer.vue 一样：数据源变化 -> 节点被替换(config 变成新对象) -> computed 重算
+  const containerConfig = ref<any>({ iteratorData: ds.data.list, items: templateNodes });
+
+  const containerComp = defineComponent({
+    setup() {
+      const configs = computed(() =>
+        (containerConfig.value.iteratorData as any[]).map((itemData) => ({
+          items: dsm.compliedIteratorItems(itemData, containerConfig.value.items, [dsId, 'list']),
+        })),
+      );
+      return () =>
+        h(
+          'div',
+          configs.value.map((config, index) => h(itemComp, { key: index, config })),
+        );
+    },
+  });
+
+  const root = document.createElement('div');
+  const vueApp = createApp(containerComp);
+  vueApp.mount(root);
+
+  // 模拟 createDataSourceManager 的 change 处理：触发容器节点被整体替换
+  const replaceContainerNode = () => {
+    containerConfig.value = { iteratorData: ds.data.list, items: templateNodes };
+  };
+
+  return { ds, dsm, root, renderCount, rawMatrix, replaceContainerNode, unmount: () => vueApp.unmount() };
+};
+
+describe('迭代容器编译 + Vue 响应式', () => {
+  afterAll(() => {
+    DataSourceManager.clearDataSourceClass();
+  });
+
+  test('路径之外的兄弟字段是与数据源隔离的快照，不修改数据源原始数据', async () => {
+    const { dsm, root, rawMatrix, unmount } = setup();
+    await nextTick();
+
+    expect(root.querySelectorAll('.item').length).toBe(2);
+    expect(root.querySelector('.cell')?.textContent).toBe('1');
+    expect(rawMatrix).toEqual([{ v: 1 }]);
+    expect(dsm.data.ds_iter_reactivity.matrix).toBe(rawMatrix);
+
+    unmount();
+  });
+
+  test('整体替换数据源数据（setData 无 path）后，视图和子孙组件都会更新', async () => {
+    const { ds, root, replaceContainerNode, unmount } = setup();
+    await nextTick();
+
+    ds.setData([{ v: 2 }], 'matrix');
+    replaceContainerNode();
+    await nextTick();
+
+    expect(root.querySelector('.cell')?.textContent).toBe('2');
+
+    unmount();
+  });
+
+  test('按 path 原地修改兄弟字段对象内部值后，子孙组件也会更新', async () => {
+    const { ds, root, renderCount, replaceContainerNode, unmount } = setup();
+    await nextTick();
+    const cellRenderBefore = renderCount.cell;
+
+    // SimpleObservedData 按路径更新为原地修改，matrix[0] 的引用不变
+    ds.setData(9, 'matrix.0.v');
+    replaceContainerNode();
+    await nextTick();
+
+    // Item 一定会因 config 换新对象而重新渲染
+    expect(renderCount.item).toBeGreaterThan(2);
+    // 兄弟字段是新的快照，子孙组件的 props 会变化并拿到最新值
+    expect(renderCount.cell).toBeGreaterThan(cellRenderBefore);
+    expect(root.querySelector('.cell')?.textContent).toBe('9');
+
+    unmount();
+  });
+});
diff --git a/packages/data-source/tests/utils.spec.ts b/packages/data-source/tests/utils.spec.ts
index 07961474..fe61822d 100644
--- a/packages/data-source/tests/utils.spec.ts
+++ b/packages/data-source/tests/utils.spec.ts
@@ -193,6 +193,63 @@ describe('createIteratorContentData', () => {
     });
     expect(ctxData.ds.a.c.a).toBe(1);
   });
+
+  test('不修改原始数据源数据', () => {
+    const dsData: any = {
+      ds: {
+        a: [{ b: 0, c: [{ a: 1 }] }],
+        obj: { x: { y: 1 }, z: 2 },
+        b: 2,
+      },
+    };
+    const snapshot = JSON.parse(JSON.stringify(dsData));
+
+    const ctxData: any = createIteratorContentData({ a: 1 }, 'ds', ['a', 'c'], dsData);
+    expect(ctxData.ds.a.c).toEqual({ a: 1 });
+
+    const objCtx: any = createIteratorContentData({ n: 1 }, 'ds', ['obj', 'x'], dsData);
+    expect(objCtx.ds.obj.x).toEqual({ n: 1 });
+    expect(objCtx.ds.obj.z).toBe(2);
+    expect(objCtx.ds.b).toBe(2);
+
+    expect(dsData).toEqual(snapshot);
+    expect(ctxData.ds).not.toBe(dsData.ds);
+    expect(objCtx.ds.obj).not.toBe(dsData.ds.obj);
+  });
+
+  test('路径之外的对象型字段惰性深拷贝：与原数据隔离、多次读取引用稳定、可被覆盖', () => {
+    const dsData: any = { ds: { a: [{ b: 1 }], matrix: [{ v: 1 }], n: 1 } };
+
+    const ctxData: any = createIteratorContentData({ b: 1 }, 'ds', ['a'], dsData);
+
+    expect(ctxData.ds.n).toBe(1);
+    const { matrix } = ctxData.ds;
+    expect(matrix).toEqual([{ v: 1 }]);
+    expect(matrix).not.toBe(dsData.ds.matrix);
+    expect(matrix[0]).not.toBe(dsData.ds.matrix[0]);
+    expect(ctxData.ds.matrix).toBe(matrix);
+
+    // 修改拷贝不影响原数据，原地修改原数据也不影响已读取过的快照
+    matrix[0].v = 2;
+    expect(dsData.ds.matrix[0].v).toBe(1);
+    dsData.ds.matrix[0].v = 3;
+    expect(ctxData.ds.matrix[0].v).toBe(2);
+
+    // 每次创建的上下文拿到的都是新的引用
+    expect(createIteratorContentData({ b: 1 }, 'ds', ['a'], dsData).ds).not.toBe(ctxData.ds);
+    expect((createIteratorContentData({ b: 1 }, 'ds', ['a'], dsData) as any).ds.matrix).not.toBe(dsData.ds.matrix);
+
+    // 支持覆盖，对象展开可枚举
+    ctxData.ds.matrix = 'x';
+    expect(ctxData.ds.matrix).toBe('x');
+    expect(Object.keys(ctxData.ds)).toEqual(expect.arrayContaining(['a', 'matrix', 'n']));
+  });
+
+  test('数据源数据或路径中间层缺失时不抛错', () => {
+    expect((createIteratorContentData({ a: 1 }, 'ds', ['a', 'c'], {}) as any).ds.a.c).toEqual({ a: 1 });
+    expect((createIteratorContentData({ a: 1 }, 'ds', ['a', 'c'], { ds: {} }) as any).ds.a.c).toEqual({ a: 1 });
+    expect((createIteratorContentData({ a: 1 }, 'ds', [], { ds: { b: 1 } }) as any).ds).toEqual({});
+  });
 });
 
 describe('compliedConditions', () => {