diff --git a/cocoscreator_projects/framework-tests/legacy-layer-migration/group-builder.test.mjs b/cocoscreator_projects/framework-tests/legacy-layer-migration/group-builder.test.mjs
new file mode 100644
index 0000000..8671c8b
--- /dev/null
+++ b/cocoscreator_projects/framework-tests/legacy-layer-migration/group-builder.test.mjs
@@ -0,0 +1,47 @@
+import { test } from 'node:test';
+import assert from 'node:assert/strict';
+import { buildGroupParents } from '../../scripts/legacy-layer-to-cocos-prefab.mjs';
+
+test('buildGroupParents 把同 group Spirit 归类', () => {
+  const spirits = [
+    { id: '1', group: '2', indexOfLayer: '1' },
+    { id: '405', group: '2', indexOfLayer: '2' },
+    { id: '285', group: '2', indexOfLayer: '3' },
+  ];
+  const result = buildGroupParents(spirits);
+  assert.equal(result.groupParents.length, 1, '只有一个 group=2');
+  assert.equal(result.groupParents[0].name, 'group-2');
+  assert.deepEqual(result.groupParents[0].childSpiritIds, ['1', '405', '285']);
+  assert.equal(result.rootChildSpiritIds.length, 0);
+});
+
+test('buildGroupParents 多 group 按 ID 升序', () => {
+  const spirits = [
+    { id: '1', group: '32', indexOfLayer: '1' },
+    { id: '2', group: '1', indexOfLayer: '2' },
+    { id: '3', group: '1', indexOfLayer: '3' },
+  ];
+  const result = buildGroupParents(spirits);
+  assert.deepEqual(result.groupParents.map(g => g.name), ['group-1', 'group-32']);
+});
+
+test('buildGroupParents group=0 Spirit 直挂 Layer 根', () => {
+  const spirits = [
+    { id: '10', group: '0', indexOfLayer: '1' },
+    { id: '20', group: '0', indexOfLayer: '2' },
+    { id: '30', group: '2', indexOfLayer: '3' },
+  ];
+  const result = buildGroupParents(spirits);
+  assert.equal(result.groupParents.length, 1);
+  assert.deepEqual(result.rootChildSpiritIds, ['10', '20']);
+});
+
+test('buildGroupParents 按 IndexOfLayer 排序子节点', () => {
+  const spirits = [
+    { id: 'c', group: '1', indexOfLayer: '3' },
+    { id: 'a', group: '1', indexOfLayer: '1' },
+    { id: 'b', group: '1', indexOfLayer: '2' },
+  ];
+  const result = buildGroupParents(spirits);
+  assert.deepEqual(result.groupParents[0].childSpiritIds, ['a', 'b', 'c']);
+});
\ No newline at end of file
diff --git a/cocoscreator_projects/scripts/legacy-layer-to-cocos-prefab.mjs b/cocoscreator_projects/scripts/legacy-layer-to-cocos-prefab.mjs
index 1d64032..ba30514 100644
--- a/cocoscreator_projects/scripts/legacy-layer-to-cocos-prefab.mjs
+++ b/cocoscreator_projects/scripts/legacy-layer-to-cocos-prefab.mjs
@@ -96,3 +96,44 @@ export function computeContentSize(spirit) {
     height: parseFloat(spirit.h || '0'),
   };
 }
+
+/**
+ * 将 Spirit 记录按 BelongGroupID 归类, 生成 group-X 父节点集合 + Layer 根直挂子节点.
+ *
+ * 规则:
+ *   - BelongGroupID === '0' (或缺失) → 直挂 Layer 根, 不进任何 group 父节点
+ *   - BelongGroupID > 0 → 归入对应 group-<N> 父节点
+ *   - group 父节点按 ID 升序排列; 同 group 内子节点按 IndexOfLayer 升序
+ *   - 命名保留原 BelongGroupID 值, 不重排
+ *
+ * 数据源权威: IndexOfLayer 缺失视作 0 (XML 中该字段由 readLayerXml 提供, 必有值).
+ *
+ * @param {Array<{ id?: string, group?: string, indexOfLayer?: string }>} spirits
+ * @returns {{ groupParents: Array<{ name: string, childSpiritIds: string[] }>, rootChildSpiritIds: string[] }}
+ */
+export function buildGroupParents(spirits) {
+  const groupMap = new Map(); // group_id -> [{ spiritId, index }]
+  const rootSpirits = [];
+
+  for (const s of spirits) {
+    if (s.group === '0' || !s.group) {
+      rootSpirits.push({ spiritId: s.id, index: parseInt(s.indexOfLayer || '0', 10) });
+    } else {
+      if (!groupMap.has(s.group)) groupMap.set(s.group, []);
+      groupMap.get(s.group).push({ spiritId: s.id, index: parseInt(s.indexOfLayer || '0', 10) });
+    }
+  }
+
+  const groupParents = Array.from(groupMap.entries())
+    .sort(([a], [b]) => parseInt(a, 10) - parseInt(b, 10))
+    .map(([gid, items]) => ({
+      name: `group-${gid}`,
+      childSpiritIds: items.sort((a, b) => a.index - b.index).map(x => x.spiritId),
+    }));
+
+  const rootChildSpiritIds = rootSpirits
+    .sort((a, b) => a.index - b.index)
+    .map(x => x.spiritId);
+
+  return { groupParents, rootChildSpiritIds };
+}