diff --git a/common/changes/@visactor/vtable-gantt/fix-issue-4631-set-records-project-times_2026-09-20-16-00.json b/common/changes/@visactor/vtable-gantt/fix-issue-4631-set-records-project-times_2026-09-20-16-00.json
new file mode 100644
index 0000000000..db207f1fba
--- /dev/null
+++ b/common/changes/@visactor/vtable-gantt/fix-issue-4631-set-records-project-times_2026-09-20-16-00.json
@@ -0,0 +1,11 @@
+{
+  "changes": [
+    {
+      "comment": "fix(gantt): recalculate project task dates when setting records",
+      "type": "patch",
+      "packageName": "@visactor/vtable-gantt"
+    }
+  ],
+  "packageName": "@visactor/vtable-gantt",
+  "email": "892739385@qq.com"
+}
diff --git a/packages/vtable-gantt/__tests__/gantt-set-records.test.ts b/packages/vtable-gantt/__tests__/gantt-set-records.test.ts
new file mode 100644
index 0000000000..17560defa9
--- /dev/null
+++ b/packages/vtable-gantt/__tests__/gantt-set-records.test.ts
@@ -0,0 +1,65 @@
+// @ts-nocheck
+
+global.__VERSION__ = 'none';
+
+import { Gantt } from '../src';
+
+describe('gantt setRecords', () => {
+  test('recalculates project task dates from new child records', () => {
+    const gantt = {
+      records: [],
+      options: {},
+      parsedOptions: {
+        startDateField: 'start',
+        endDateField: 'end',
+        dateFormat: 'yyyy-mm-dd',
+        reverseSortedTimelineScales: [{ unit: 'day', step: 1 }],
+        sortedTimelineScales: [{ unit: 'day', step: 1 }]
+      },
+      data: {
+        setRecords: jest.fn()
+      },
+      taskListTableInstance: {
+        records: [],
+        setRecords(records) {
+          this.records = records;
+        }
+      },
+      _syncPropsFromTable: jest.fn(),
+      _generateTimeLineDateMap: jest.fn(),
+      _updateSize: jest.fn(),
+      scenegraph: {
+        refreshAll: jest.fn(),
+        setX: jest.fn(),
+        setY: jest.fn()
+      },
+      verticalSplitResizeLine: { style: {} },
+      drawHeight: 400,
+      stateManager: {
+        scroll: {
+          horizontalBarPos: 0,
+          verticalBarPos: 0
+        }
+      }
+    };
+
+    const nextRecords = [
+      {
+        id: 2,
+        name: 'Planning',
+        type: 'project',
+        children: [
+          { id: 3, name: 'Design', start: '2024-11-15', end: '2024-11-18' },
+          { id: 4, name: 'Review', start: '2024-11-12', end: '2024-11-20' }
+        ]
+      }
+    ];
+
+    Gantt.prototype.setRecords.call(gantt, nextRecords);
+
+    expect(gantt.records[0].start).toBe('2024-11-12');
+    expect(gantt.records[0].end).toBe('2024-11-20');
+    expect(gantt.taskListTableInstance.records[0].start).toBe('2024-11-12');
+    expect(gantt.taskListTableInstance.records[0].end).toBe('2024-11-20');
+  });
+});
diff --git a/packages/vtable-gantt/examples/gantt/issue-4631-set-records-project.ts b/packages/vtable-gantt/examples/gantt/issue-4631-set-records-project.ts
new file mode 100644
index 0000000000..61fe2b8281
--- /dev/null
+++ b/packages/vtable-gantt/examples/gantt/issue-4631-set-records-project.ts
@@ -0,0 +1,70 @@
+import type { GanttConstructorOptions } from '../../src';
+import { Gantt, TYPES } from '../../src';
+
+const CONTAINER_ID = 'vTable';
+
+const projectRecords = [
+  {
+    id: 2,
+    name: 'Planning',
+    type: 'project',
+    children: [
+      { id: 3, name: 'Design', start: '2024-11-15', end: '2024-11-18' },
+      { id: 4, name: 'Review', start: '2024-11-12', end: '2024-11-20' }
+    ]
+  }
+];
+
+export function createTable() {
+  const container = document.getElementById(CONTAINER_ID);
+  if (!container) {
+    return;
+  }
+  const status = document.createElement('div');
+  const updateButton = document.createElement('button');
+
+  status.style.cssText = 'height: 32px; line-height: 32px; font: 14px sans-serif;';
+  updateButton.textContent = 'Set project records';
+  updateButton.style.cssText = 'margin-bottom: 8px; padding: 6px 12px; cursor: pointer;';
+  container.parentElement?.insertBefore(status, container);
+  container.parentElement?.insertBefore(updateButton, container);
+
+  const options: GanttConstructorOptions = {
+    records: [{ id: 1, name: 'Initial task', start: '2024-11-01', end: '2024-11-02' }],
+    taskListTable: {
+      columns: [
+        { field: 'name', title: 'Task', width: 160, tree: true },
+        { field: 'start', title: 'Start', width: 110 },
+        { field: 'end', title: 'End', width: 110 }
+      ],
+      tableWidth: 380
+    },
+    tasksShowMode: TYPES.TasksShowMode.Tasks_Separate,
+    taskBar: {
+      startDateField: 'start',
+      endDateField: 'end',
+      labelText: '{name}'
+    },
+    timelineHeader: {
+      colWidth: 50,
+      scales: [
+        { unit: 'week', step: 1, startOfWeek: 'monday' },
+        { unit: 'day', step: 1 }
+      ]
+    },
+    minDate: '2024-11-01',
+    maxDate: '2024-11-30'
+  };
+
+  const ganttInstance = new Gantt(container, options);
+  window.ganttInstance = ganttInstance;
+
+  const updateRecords = () => {
+    ganttInstance.setRecords(projectRecords);
+    const project = ganttInstance.records[0];
+    status.textContent = `Project range: ${project.start ?? 'missing'} - ${project.end ?? 'missing'}`;
+  };
+
+  updateButton.addEventListener('click', updateRecords);
+  updateRecords();
+}
diff --git a/packages/vtable-gantt/examples/menu.ts b/packages/vtable-gantt/examples/menu.ts
index 1bcfe17a99..560d06f343 100644
--- a/packages/vtable-gantt/examples/menu.ts
+++ b/packages/vtable-gantt/examples/menu.ts
@@ -182,6 +182,10 @@ export const menus = [
   {
     path: 'gantt',
     name: 'issue-4778-taskbar-relative-rect'
+  },
+  {
+    path: 'gantt',
+    name: 'issue-4631-set-records-project'
   }
   //   ]
   // }
diff --git a/packages/vtable-gantt/src/Gantt.ts b/packages/vtable-gantt/src/Gantt.ts
index 0cfcca00c1..9fe3966529 100644
--- a/packages/vtable-gantt/src/Gantt.ts
+++ b/packages/vtable-gantt/src/Gantt.ts
@@ -1510,6 +1510,7 @@ export class Gantt extends EventTarget {
   }
   setRecords(records: any[]) {
     this.records = records;
+    initProjectTaskTimes(this);
     this.data.setRecords(records);
     updateOptionsWhenRecordChanged(this);
     this.taskListTableInstance.setRecords(records);