diff --git a/nl-module-lms/nl-module-lms-api/src/main/java/cn/code/nl/module/lms/enums/ErrorCodeConstants.java b/nl-module-lms/nl-module-lms-api/src/main/java/cn/code/nl/module/lms/enums/ErrorCodeConstants.java
index e843da03..63297b73 100644
--- a/nl-module-lms/nl-module-lms-api/src/main/java/cn/code/nl/module/lms/enums/ErrorCodeConstants.java
+++ b/nl-module-lms/nl-module-lms-api/src/main/java/cn/code/nl/module/lms/enums/ErrorCodeConstants.java
@@ -58,4 +58,6 @@ public interface ErrorCodeConstants {
     ErrorCode DAILY_PLAN_WEIGHT_NOT_POSITIVE = new ErrorCode(33, "日计划权重必须为正整数");
     ErrorCode DAILY_PLAN_CANCEL_OR_RESUME_REASON_EMPTY = new ErrorCode(34, "取消或恢复原因不能为空");
     ErrorCode DAILY_PLAN_ERP_TOKEN_ERROR = new ErrorCode(35, "ERP日计划接口令牌错误");
+    ErrorCode DAILY_PLAN_QTY_EXCEEDS_LIMIT = new ErrorCode(36, "日计划数量超过系统支持范围");
+    ErrorCode DAILY_PLAN_CODE_GENERATE_FAILED = new ErrorCode(37, "日计划编码生成失败");
 }
diff --git a/nl-module-lms/nl-module-lms-server/src/main/java/cn/code/nl/module/lms/service/dailyplan/DailyPlanServiceImpl.java b/nl-module-lms/nl-module-lms-server/src/main/java/cn/code/nl/module/lms/service/dailyplan/DailyPlanServiceImpl.java
index 2dda42f0..21c14aca 100644
--- a/nl-module-lms/nl-module-lms-server/src/main/java/cn/code/nl/module/lms/service/dailyplan/DailyPlanServiceImpl.java
+++ b/nl-module-lms/nl-module-lms-server/src/main/java/cn/code/nl/module/lms/service/dailyplan/DailyPlanServiceImpl.java
@@ -5,14 +5,31 @@ import cn.code.nl.framework.common.pojo.CommonResult;
 import cn.code.nl.framework.common.pojo.PageResult;
 import cn.code.nl.module.base.api.codegen.CodeGenApi;
 import cn.code.nl.module.base.api.codegen.dto.CodeGenerateReqDTO;
-import cn.code.nl.module.lms.controller.admin.dailyplan.vo.*;
+import cn.code.nl.module.lms.controller.admin.dailyplan.vo.DailyPlanAppendReqVO;
+import cn.code.nl.module.lms.controller.admin.dailyplan.vo.DailyPlanCreateReqVO;
+import cn.code.nl.module.lms.controller.admin.dailyplan.vo.DailyPlanOperationLogRespVO;
+import cn.code.nl.module.lms.controller.admin.dailyplan.vo.DailyPlanPageReqVO;
+import cn.code.nl.module.lms.controller.admin.dailyplan.vo.DailyPlanReasonReqVO;
+import cn.code.nl.module.lms.controller.admin.dailyplan.vo.DailyPlanRespVO;
+import cn.code.nl.module.lms.controller.admin.dailyplan.vo.DailyPlanSortUpdateReqVO;
+import cn.code.nl.module.lms.controller.admin.dailyplan.vo.DailyPlanStartReqVO;
+import cn.code.nl.module.lms.controller.admin.dailyplan.vo.DailyPlanStrategyRespVO;
+import cn.code.nl.module.lms.controller.admin.dailyplan.vo.DailyPlanStrategyUpdateReqVO;
+import cn.code.nl.module.lms.controller.admin.dailyplan.vo.DailyPlanUpdateReqVO;
+import cn.code.nl.module.lms.controller.admin.dailyplan.vo.DailyPlanVersionReqVO;
+import cn.code.nl.module.lms.controller.admin.dailyplan.vo.DailyPlanWeightUpdateReqVO;
+import cn.code.nl.module.lms.controller.admin.dailyplan.vo.DailyPlanWorkPageReqVO;
 import cn.code.nl.module.lms.dal.dataobject.dailyplan.DailyPlanDO;
 import cn.code.nl.module.lms.dal.dataobject.dailyplan.DailyPlanOperationLogDO;
 import cn.code.nl.module.lms.dal.dataobject.dailyplan.DailyPlanStrategyDO;
 import cn.code.nl.module.lms.dal.mysql.dailyplan.DailyPlanMapper;
 import cn.code.nl.module.lms.dal.mysql.dailyplan.DailyPlanOperationLogMapper;
 import cn.code.nl.module.lms.dal.mysql.dailyplan.DailyPlanStrategyMapper;
-import cn.code.nl.module.lms.enums.*;
+import cn.code.nl.module.lms.enums.DailyPlanOrderStatusEnum;
+import cn.code.nl.module.lms.enums.DailyPlanSourceTypeEnum;
+import cn.code.nl.module.lms.enums.DailyPlanStrategyModeEnum;
+import cn.code.nl.module.lms.enums.DailyPlanStrategyTypeEnum;
+import cn.code.nl.module.lms.enums.DailyPlanWorkStatusEnum;
 import cn.hutool.core.util.StrUtil;
 import com.baomidou.mybatisplus.core.toolkit.IdWorker;
 import jakarta.annotation.Resource;
@@ -28,7 +45,12 @@ import java.util.Set;
 
 import static cn.code.nl.framework.common.exception.util.ServiceExceptionUtil.exception;
 import static cn.code.nl.framework.security.core.util.SecurityFrameworkUtils.getLoginUserId;
-import static cn.code.nl.module.lms.enums.ErrorCodeConstants.*;
+import static cn.code.nl.module.lms.enums.ErrorCodeConstants.DAILY_PLAN_CODE_GENERATE_FAILED;
+import static cn.code.nl.module.lms.enums.ErrorCodeConstants.DAILY_PLAN_NOT_EXISTS;
+import static cn.code.nl.module.lms.enums.ErrorCodeConstants.DAILY_PLAN_QTY_EXCEEDS_LIMIT;
+import static cn.code.nl.module.lms.enums.ErrorCodeConstants.DAILY_PLAN_STATUS_OPERATION_NOT_ALLOWED;
+import static cn.code.nl.module.lms.enums.ErrorCodeConstants.DAILY_PLAN_STRATEGY_NOT_EXISTS;
+import static cn.code.nl.module.lms.enums.ErrorCodeConstants.DAILY_PLAN_VERSION_CONFLICT;
 
 /** LMS 日计划服务实现。 */
 @Service
@@ -140,9 +162,15 @@ public class DailyPlanServiceImpl implements DailyPlanService {
         CodeGenerateReqDTO codeReq = new CodeGenerateReqDTO();
         codeReq.setRuleCode("LMS_DAILY_PLAN_CODE");
         CommonResult<String> codeResult = codeGenApi.generate(codeReq);
+        if (codeResult == null) {
+            throw exception(DAILY_PLAN_CODE_GENERATE_FAILED);
+        }
         if (!codeResult.isSuccess()) {
             throw new ServiceException(codeResult.getCode(), codeResult.getMsg());
         }
+        if (StrUtil.isEmpty(codeResult.getData())) {
+            throw exception(DAILY_PLAN_CODE_GENERATE_FAILED);
+        }
         String userId = String.valueOf(getLoginUserId());
         DailyPlanDO plan = new DailyPlanDO();
         plan.setDailyPlanId(IdWorker.getId());
@@ -183,7 +211,7 @@ public class DailyPlanServiceImpl implements DailyPlanService {
         DailyPlanDO update = newUpdate(current);
         update.setOrderStatus(DailyPlanOrderStatusEnum.IN_PROGRESS.getCode());
         update.setOrderStartTime(LocalDateTime.now());
-        update.setAppendQty(current.getAppendQty() + reqVO.getAppendQty());
+        update.setAppendQty(safeAddQuantity(current.getAppendQty(), reqVO.getAppendQty()));
         checkAffected(dailyPlanMapper.updateStateWithVersion(update));
         insertLog(current.getDailyPlanId(), TARGET_ORDER, TYPE_START, String.valueOf(current.getOrderStatus()),
                 String.valueOf(update.getOrderStatus()), reqVO.getAppendQty(), null);
@@ -196,7 +224,7 @@ public class DailyPlanServiceImpl implements DailyPlanService {
         DailyPlanDO current = validateVersion(reqVO.getId(), reqVO.getVersion());
         validateOrderStatus(current, DailyPlanOrderStatusEnum.IN_PROGRESS, "追加数量");
         DailyPlanDO update = newUpdate(current);
-        update.setAppendQty(current.getAppendQty() + reqVO.getAppendQty());
+        update.setAppendQty(safeAddQuantity(current.getAppendQty(), reqVO.getAppendQty()));
         checkAffected(dailyPlanMapper.updateStateWithVersion(update));
         insertLog(current.getDailyPlanId(), TARGET_QUANTITY, TYPE_APPEND, String.valueOf(current.getAppendQty()),
                 String.valueOf(update.getAppendQty()), reqVO.getAppendQty(), null);
@@ -492,6 +520,15 @@ public class DailyPlanServiceImpl implements DailyPlanService {
         }
     }
 
+    /** 安全相加日计划数量，避免整数溢出。 */
+    private int safeAddQuantity(Integer left, Integer right) {
+        long result = (long) left + right;
+        if (result > Integer.MAX_VALUE) {
+            throw exception(DAILY_PLAN_QTY_EXCEEDS_LIMIT);
+        }
+        return (int) result;
+    }
+
     /** 新增日计划操作日志，操作时间由数据库生成。 */
     private void insertLog(Long dailyPlanId, String target, String type, String beforeValue, String afterValue,
                            Integer changeQty, String reason) {
@@ -523,7 +560,7 @@ public class DailyPlanServiceImpl implements DailyPlanService {
         response.setMaterialSpec(plan.getMaterialSpec());
         response.setPlanQty(plan.getPlanQty());
         response.setAppendQty(plan.getAppendQty());
-        response.setTotalQty(plan.getPlanQty() + plan.getAppendQty());
+        response.setTotalQty(safeAddQuantity(plan.getPlanQty(), plan.getAppendQty()));
         response.setStockedQty(plan.getStockedQty());
         response.setSleevedQty(plan.getSleevedQty());
         response.setPackingInfo(plan.getPackingInfo());