diff --git a/src/qc/qc.service.spec.ts b/src/qc/qc.service.spec.ts
index b2cbb10..826808a 100644
--- a/src/qc/qc.service.spec.ts
+++ b/src/qc/qc.service.spec.ts
@@ -658,12 +658,16 @@ describe('QcService.handleAbnormal', () => {
     expect(recordAbnormalUpdate).not.toHaveBeenCalled();
   });
 
-  it('处理 → 更新 handle_status/handle_result', async () => {
+  it('处理 → 更新 handle_status/handle_result + 坐标 Decimal → string', async () => {
     const recordAbnormalFindUnique = vi.fn().mockResolvedValue({ id: 'a1', handleStatus: 'open' });
-    const recordAbnormalUpdate = vi.fn().mockResolvedValue({ id: 'a1' });
+    const recordAbnormalUpdate = vi.fn().mockResolvedValue({
+      id: 'a1',
+      visitLat: { toString: () => '25.010000' },
+      visitLng: null,
+    });
     const { service } = makeService({ recordAbnormalFindUnique, recordAbnormalUpdate });
 
-    await runWithRequestContext(ctx, () =>
+    const res = await runWithRequestContext(ctx, () =>
       service.handleAbnormal('a1', { handleStatus: 'closed', handleResult: '已通知家属' }),
     );
 
@@ -672,6 +676,7 @@ describe('QcService.handleAbnormal', () => {
       where: { id: 'a1' },
       data: { handleStatus: 'closed', handleResult: '已通知家属' },
     });
+    expect(res).toMatchObject({ id: 'a1', visitLat: '25.010000', visitLng: null });
   });
 
   it('handleResult 缺省 → 更新为 null', async () => {
diff --git a/src/qc/qc.service.ts b/src/qc/qc.service.ts
index dd96bfb..0ed7982 100644
--- a/src/qc/qc.service.ts
+++ b/src/qc/qc.service.ts
@@ -241,16 +241,17 @@ export class QcService {
     });
   }
 
-  /** 异常处理：质控员更新 handle_status/handle_result。 */
+  /** 异常处理：质控员更新 handle_status/handle_result；返回前坐标 Decimal → string。 */
   async handleAbnormal(id: string, dto: HandleAbnormalDto) {
     const abnormal = await this.prisma.client.recordAbnormal.findUnique({ where: { id } });
     if (!abnormal) {
       throw new BusinessException(ErrorCodes.ABNORMAL_NOT_FOUND, '异常上报不存在', HttpStatus.NOT_FOUND);
     }
-    return this.prisma.client.recordAbnormal.update({
+    const updated = await this.prisma.client.recordAbnormal.update({
       where: { id },
       data: { handleStatus: dto.handleStatus, handleResult: dto.handleResult ?? null },
     });
+    return this.serializeAbnormal(updated);
   }
 
   /** 批量放行：安全边界（异常/未执行/加项/时长过短/已补正）任一命中 → QC_BATCH_UNSAFE；否则逐条 pass。 */
@@ -334,6 +335,15 @@ export class QcService {
     }
   }
 
+  /** 异常到访坐标 Decimal → string（null 保持 null），复用 abnormal 模块 list/report 口径。 */
+  private serializeAbnormal(abnormal: Record<string, any>): Record<string, any> {
+    return {
+      ...abnormal,
+      visitLat: abnormal.visitLat != null ? abnormal.visitLat.toString() : null,
+      visitLng: abnormal.visitLng != null ? abnormal.visitLng.toString() : null,
+    };
+  }
+
   /** Prisma Decimal 坐标转字符串（null 保持 null），复用 C3 口径，含异常到访坐标。 */
   private serializeRecord(record: Record<string, any>): Record<string, any> {
     const serialized: Record<string, any> = {