diff --git a/ruoyi-oa/src/main/java/com/ruoyi/oa/service/impl/OaProjectScheduleStepServiceImpl.java b/ruoyi-oa/src/main/java/com/ruoyi/oa/service/impl/OaProjectScheduleStepServiceImpl.java
index cad3be8..fadea2d 100644
--- a/ruoyi-oa/src/main/java/com/ruoyi/oa/service/impl/OaProjectScheduleStepServiceImpl.java
+++ b/ruoyi-oa/src/main/java/com/ruoyi/oa/service/impl/OaProjectScheduleStepServiceImpl.java
@@ -122,16 +122,29 @@ public class OaProjectScheduleStepServiceImpl implements IOaProjectScheduleStepS
      */
     @Override
     public Boolean updateByBo(OaProjectScheduleStepBo bo) {
-
-        // 除了做更新还需要编辑文件权限将涉及到的所有文件 都涉及到userId
+        // 1. 转换实体并校验
         OaProjectScheduleStep update = BeanUtil.toBean(bo, OaProjectScheduleStep.class);
         validEntityBeforeSave(update);
-        //查询end_time结束时间是不是空 如果是空则证明是第一次修改需要给end_time赋值也就是新的结束时间原来结束时间不变
-        OaProjectScheduleStep oaProjectScheduleStep = baseMapper.selectOne(new LambdaQueryWrapper<OaProjectScheduleStep>().eq(OaProjectScheduleStep::getTrackId, update.getTrackId()));
-        if (oaProjectScheduleStep.getEndTime() == null) {
+
+        // 2. 查询原数据（先判断 trackId 是否存在）
+        Long trackId = update.getTrackId();
+        if (trackId == null) {
+            throw new IllegalArgumentException("更新主键 trackId 不能为空");
+        }
+        OaProjectScheduleStep original = baseMapper.selectById(trackId); // 推荐用 selectById 更简洁
+        if (original == null) {
+            // 处理查询不到的情况（例如抛异常或返回失败）
+            throw new RuntimeException("未找到 ID 为 " + trackId + " 的项目进度步骤记录");
+        }
+
+        // 3. 处理结束时间逻辑（此时 original 一定非 null，可安全调用方法）
+        if (original.getEndTime() == null) {
+            // 首次修改：设置结束时间和原始结束时间
             update.setEndTime(bo.getEndTime());
             update.setOriginalEndTime(bo.getEndTime());
         }
+
+        // 4. 执行更新
         return baseMapper.updateById(update) > 0;
     }