diff --git a/apps/desktop/src/composables/__tests__/useDataGridExport.spec.ts b/apps/desktop/src/composables/__tests__/useDataGridExport.spec.ts
index 8340df9d84..eaa0f3dece 100644
--- a/apps/desktop/src/composables/__tests__/useDataGridExport.spec.ts
+++ b/apps/desktop/src/composables/__tests__/useDataGridExport.spec.ts
@@ -7,7 +7,7 @@ import { copyToClipboard } from "@/lib/common/clipboard";
 import type { DataGridTableMeta } from "@/lib/dataGrid/dataGridSql";
 import type { CellSelectionMatrix, SelectionData } from "@/lib/dataGrid/gridSelection";
 import type { CellValue } from "@/lib/dataGrid/cellValue";
-import { extractDataGridSelection } from "@/lib/backend/api";
+import { extractDataGridSelection, exportQueryResultJson } from "@/lib/backend/api";
 import { DEFAULT_DATA_GRID_EXTRACTOR_OPTIONS } from "@/lib/dataGrid/dataGridCopyExtractor";
 import { clearDataGridClipboardCopy, parseDataGridClipboard } from "@/lib/dataGrid/dataGridClipboard";
 
@@ -46,6 +46,7 @@ vi.mock("@/lib/backend/api", async (importOriginal) => {
   return {
     ...original,
     extractDataGridSelection: vi.fn(),
+    exportQueryResultJson: vi.fn(),
   };
 });
 
@@ -70,6 +71,7 @@ function createMongoExportState(options: {
   mongoUpdateTarget?: false;
   contextColumn?: number;
   syntheticContext?: boolean;
+  fullExportResult?: UseDataGridExportOptions["fullExportResult"];
 }) {
   const items = options.items ?? [options.item];
   const selectedRowIds = options.selectedRowIds ?? new Set<number>();
@@ -99,6 +101,7 @@ function createMongoExportState(options: {
     getRowItem: (rowId) => items.find((item) => item.id === rowId),
     selectedRowIds: ref(selectedRowIds),
     hasRowSelection: computed(() => selectedRowIds.size > 0),
+    fullExportResult: options.fullExportResult,
   };
   return useDataGridExport(state);
 }
@@ -1509,6 +1512,33 @@ describe("useDataGridExport prepared row statements", () => {
     expect(extractDataGridSelection).not.toHaveBeenCalled();
     expect(copyToClipboard).not.toHaveBeenCalled();
   });
+
+  it("preserves Mongo Extended JSON objects and dates in JSON exports", async () => {
+    const columns = ["_id", "valueMap", "createdTime"];
+    const mongoCopyDocument = {
+      _id: { $oid: "6a9fb51db2f0c46b94002f26" },
+      valueMap: { field1: "10147E", field2: "0" },
+      createdTime: { $date: "2026-09-08T07:11:25.458Z" },
+    };
+    const item = { ...row(["6a9fb51db2f0c46b94002f26", JSON.stringify(mongoCopyDocument.valueMap), 'ISODate("2026-09-08T07:11:25.458Z")']), sourceIndex: 0 };
+    const state = createMongoExportState({
+      columns,
+      item,
+      mongoDocuments: [mongoCopyDocument],
+      fullExportResult: async () => ({
+        columns,
+        column_types: ["", "", "datetime"],
+        rows: [item.data as [string, string, string]],
+        mongo_copy_documents: [mongoCopyDocument],
+        affected_rows: 1,
+        execution_time_ms: 1,
+      }),
+    });
+
+    await state.exportJson();
+
+    expect(exportQueryResultJson).toHaveBeenCalledWith(expect.any(String), columns, [[mongoCopyDocument._id, mongoCopyDocument.valueMap, mongoCopyDocument.createdTime]]);
+  });
 });
 
 // issue #7471：文本型 MySQL VARBINARY 复制单元格/多选/整行时，外部剪贴板应呈现原始字符串；
diff --git a/apps/desktop/src/composables/useDataGridExport.ts b/apps/desktop/src/composables/useDataGridExport.ts
index bdd2d73f50..0279a898b2 100644
--- a/apps/desktop/src/composables/useDataGridExport.ts
+++ b/apps/desktop/src/composables/useDataGridExport.ts
@@ -331,7 +331,7 @@ export function useDataGridExport(options: UseDataGridExportOptions) {
     });
   }
 
-  function normalizeCompleteLocalResult(result: QueryResult): { columns: string[]; columnTypes: string[]; columnComments: Array<string | undefined>; rows: CellValue[][] } {
+  function normalizeCompleteLocalResult(result: QueryResult): { columns: string[]; columnTypes: string[]; columnComments: Array<string | undefined>; rows: CellValue[][]; mongoCopyDocuments?: unknown[] } {
     const hiddenColumnIndexes = new Set(result.hidden_column_indexes ?? []);
     const exportedColumnIndexes = result.columns.map((_, index) => index).filter((index) => !hiddenColumnIndexes.has(index));
     const hasHiddenColumns = exportedColumnIndexes.length !== result.columns.length;
@@ -345,15 +345,34 @@ export function useDataGridExport(options: UseDataGridExportOptions) {
       columnTypes: hasHiddenColumns ? exportedColumnIndexes.map((index) => result.column_types?.[index] ?? "") : (result.column_types ?? []),
       columnComments: hasHiddenColumns ? exportedColumnIndexes.map((index) => allXlsxColumnComments.value[index]) : [...allXlsxColumnComments.value],
       rows: hasHiddenColumns ? rows.map((row) => exportedColumnIndexes.map((index) => row[index])) : rows,
+      mongoCopyDocuments: result.mongo_copy_documents?.slice(0, rows.length),
     };
   }
 
+  function mongoDocumentRowsForJson(columnsToExport: string[], rows: CellValue[][], documents: unknown[] | undefined): CellValue[][] {
+    if (databaseType.value !== "mongodb" || !documents || documents.length !== rows.length) return rows;
+    return rows.map((row, rowIndex) => {
+      const document = documents[rowIndex];
+      if (!document || typeof document !== "object" || Array.isArray(document)) return row;
+      const source = document as Record<string, unknown>;
+      return columnsToExport.map((column, columnIndex) => (Object.prototype.hasOwnProperty.call(source, column) ? (source[column] as CellValue) : (row[columnIndex] ?? null)));
+    });
+  }
+
+  function mongoLocalRowsForJson(items: RowItem[]): CellValue[][] {
+    return items.map((item) => {
+      const document = rowToJsonObject(item);
+      return columns.value.map((column) => (document[column] as CellValue) ?? null);
+    });
+  }
+
   async function resultToExport(
     rowIds?: number[],
     onProgress?: (info: { rowsExported: number; totalRows: number | null }) => void,
     useFullExport = true,
     formatDateTime = true,
     headerMode: XlsxHeaderMode = "name",
+    preserveMongoExtendedJson = false,
   ): Promise<{
     columns: string[];
     columnTypes: string[];
@@ -367,7 +386,7 @@ export function useDataGridExport(options: UseDataGridExportOptions) {
       if (result) {
         const columnComments = buildXlsxHeaderOverrides(result.columns, commentsForExportColumns(result.columns), headerMode);
         return {
-          ...applyGlobalDateTimeExportFormat({ columns: result.columns, columnTypes: result.column_types ?? [], rows: result.rows }, formatDateTime),
+          ...applyGlobalDateTimeExportFormat({ columns: result.columns, columnTypes: result.column_types ?? [], rows: preserveMongoExtendedJson ? mongoDocumentRowsForJson(result.columns, result.rows, result.mongo_copy_documents) : result.rows }, formatDateTime && !preserveMongoExtendedJson),
           columnComments,
           spatialColumns: result.spatial_columns,
           spatialValues: result.spatial_values,
@@ -383,7 +402,7 @@ export function useDataGridExport(options: UseDataGridExportOptions) {
       const normalized = normalizeCompleteLocalResult(completeLocalResult.value);
       const columnComments = buildXlsxHeaderOverrides(normalized.columns, normalized.columnComments, headerMode);
       return {
-        ...applyGlobalDateTimeExportFormat({ columns: normalized.columns, columnTypes: normalized.columnTypes, rows: normalized.rows }, formatDateTime),
+        ...applyGlobalDateTimeExportFormat({ columns: normalized.columns, columnTypes: normalized.columnTypes, rows: preserveMongoExtendedJson ? mongoDocumentRowsForJson(normalized.columns, normalized.rows, normalized.mongoCopyDocuments) : normalized.rows }, formatDateTime && !preserveMongoExtendedJson),
         columnComments,
         spatialColumns: completeLocalResult.value.spatial_columns,
         spatialValues: completeLocalResult.value.spatial_values,
@@ -399,9 +418,9 @@ export function useDataGridExport(options: UseDataGridExportOptions) {
         {
           columns: columns.value,
           columnTypes: (columnTypes.value ?? []).map((type) => type ?? ""),
-          rows: exportItems.map((item) => item.data),
+          rows: preserveMongoExtendedJson && databaseType.value === "mongodb" ? mongoLocalRowsForJson(exportItems) : exportItems.map((item) => item.data),
         },
-        formatDateTime,
+        formatDateTime && !preserveMongoExtendedJson,
       ),
       columnComments: commentHeader,
       ...(spatialColumns?.length ? { spatialColumns } : {}),
@@ -842,7 +861,7 @@ export function useDataGridExport(options: UseDataGridExportOptions) {
           if (!path) return;
           outputPath = path as string;
         }
-        const result = await resultToExport(rowIds);
+        const result = await resultToExport(rowIds, undefined, true, true, "name", true);
         await api.exportQueryResultJson(outputPath, result.columns, result.rows);
         toast(t("grid.exported"));
       } catch (e: any) {
@@ -864,7 +883,7 @@ export function useDataGridExport(options: UseDataGridExportOptions) {
           if (!path) return;
           outputPath = path as string;
         }
-        const result = await resultToExport(undefined, undefined, false);
+        const result = await resultToExport(undefined, undefined, false, true, "name", true);
         await api.exportQueryResultJson(outputPath, result.columns, result.rows);
         toast(t("grid.exported"));
       } catch (e: any) {