diff --git a/src/main/java/cn/edu/hfut/rmdjzz/projectmanagement/service/ITaskService.java b/src/main/java/cn/edu/hfut/rmdjzz/projectmanagement/service/ITaskService.java
index cd0113a..7b254d4 100644
--- a/src/main/java/cn/edu/hfut/rmdjzz/projectmanagement/service/ITaskService.java
+++ b/src/main/java/cn/edu/hfut/rmdjzz/projectmanagement/service/ITaskService.java
@@ -13,6 +13,9 @@ import java.util.List;
  */
 public interface ITaskService extends IService<Task> {
     List<Task> getTaskList(String token,Integer projectId,Long fatherId) throws BadRequestException;
+    List<List<Long>> getTaskAndSubTask(Long taskId);
+    Boolean deleteTaskAndSubTask(String token, Integer projectId, Long taskId) throws BadRequestException;
+    Boolean closeTaskAndSubTask(String token, Integer projectId, Long taskId) throws  BadRequestException;
     Boolean checkHolder(Integer staffId,Long taskId);
     Boolean checkHolder(String token,Long taskId);
     List<Task> getMyTaskList(String token,Integer projectId) throws BadRequestException;
diff --git a/src/main/java/cn/edu/hfut/rmdjzz/projectmanagement/service/impl/TaskServiceImpl.java b/src/main/java/cn/edu/hfut/rmdjzz/projectmanagement/service/impl/TaskServiceImpl.java
index ade0e7a..8e107d8 100644
--- a/src/main/java/cn/edu/hfut/rmdjzz/projectmanagement/service/impl/TaskServiceImpl.java
+++ b/src/main/java/cn/edu/hfut/rmdjzz/projectmanagement/service/impl/TaskServiceImpl.java
@@ -19,6 +19,7 @@ import java.time.LocalDateTime;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Objects;
+import java.util.stream.Collectors;
 
 /**
  * @author 张韬
@@ -36,6 +37,59 @@ public class TaskServiceImpl extends ServiceImpl<TaskMapper, Task> implements IT
         return baseMapper.selectList(Wrappers.<Task>lambdaQuery().eq(Task::getTaskProjectId,projectId).eq(Task::getTaskFatherId,fatherId));
     }
 
+    @Override
+    public List<List<Long>> getTaskAndSubTask(Long taskId) {
+        List<List<Long>> resList = new ArrayList<>();
+        List<Long> res = new ArrayList<>();
+        res.add(taskId);
+        resList.add(res);
+        while(true) {
+            List<Task> list = baseMapper.selectList(Wrappers.<Task>lambdaQuery().in(Task::getTaskFatherId, res));
+            if(list == null || list.isEmpty()) break;
+            res = list.stream().map(Task::getTaskId).collect(Collectors.toList());
+            resList.add(res);
+        }
+        return resList;
+    }
+
+    @Override
+    public Boolean deleteTaskAndSubTask(String token, Integer projectId, Long taskId) throws BadRequestException{
+        if(projectGroupService.getUserLevelInGroup(token,projectId)==0) {
+            throw new BadRequestException("错误参数");
+        }
+        if(!checkHolder(token, taskId)) {
+            throw new BadRequestException("错误父级参数");
+        }
+        List<List<Long>> resList = getTaskAndSubTask(taskId);
+        try {
+            for (List<Long> list: resList) {
+                baseMapper.delete(Wrappers.<Task>lambdaQuery().in(Task::getTaskId, list));
+            }
+            return true;
+        } catch (Exception e) {
+            return false;
+        }
+    }
+
+    @Override
+    public Boolean closeTaskAndSubTask(String token, Integer projectId, Long taskId) throws BadRequestException{
+        if(projectGroupService.getUserLevelInGroup(token,projectId)==0) {
+            throw new BadRequestException("错误参数");
+        }
+        if(!checkHolder(token, taskId)) {
+            throw new BadRequestException("错误父级参数");
+        }
+        List<List<Long>> resList = getTaskAndSubTask(taskId);
+        try {
+            for (List<Long> list: resList) {
+                baseMapper.update(null, Wrappers.<Task>lambdaUpdate().in(Task::getTaskId, list).set(Task::getTaskType, "关闭"));
+            }
+            return true;
+        } catch (Exception e) {
+            return false;
+        }
+    }
+
     @Override
     public Boolean checkHolder(Integer staffId,Long taskId){
         try{