diff --git a/modules/activiti-engine/src/main/java/org/activiti/engine/impl/persistence/entity/HistoricTaskInstanceEntityManager.java b/modules/activiti-engine/src/main/java/org/activiti/engine/impl/persistence/entity/HistoricTaskInstanceEntityManager.java
index f0d14024cc6..4eb799913a5 100644
--- a/modules/activiti-engine/src/main/java/org/activiti/engine/impl/persistence/entity/HistoricTaskInstanceEntityManager.java
+++ b/modules/activiti-engine/src/main/java/org/activiti/engine/impl/persistence/entity/HistoricTaskInstanceEntityManager.java
@@ -101,12 +101,22 @@ public HistoricTaskInstanceEntity findHistoricTaskInstanceById(String taskId) {
     return null;
   }
   
+  @SuppressWarnings("unchecked")
+  public List<HistoricTaskInstance> findHistoricTasksByParentTaskId(String parentTaskId) {
+    return getDbSqlSession().selectList("selectHistoricTasksByParentTaskId", parentTaskId);
+  }
+  
   public void deleteHistoricTaskInstanceById(String taskId) {
     if (getHistoryManager().isHistoryEnabled()) {
       HistoricTaskInstanceEntity historicTaskInstance = findHistoricTaskInstanceById(taskId);
-      if(historicTaskInstance!=null) {
+      if (historicTaskInstance != null) {
         CommandContext commandContext = Context.getCommandContext();
         
+        List<HistoricTaskInstance> subTasks = findHistoricTasksByParentTaskId(taskId);
+        for (HistoricTaskInstance subTask: subTasks) {
+          deleteHistoricTaskInstanceById(subTask.getId());
+        }
+        
         commandContext
           .getHistoricDetailEntityManager()
           .deleteHistoricDetailsByTaskId(taskId);
diff --git a/modules/activiti-engine/src/main/resources/org/activiti/db/mapping/entity/HistoricTaskInstance.xml b/modules/activiti-engine/src/main/resources/org/activiti/db/mapping/entity/HistoricTaskInstance.xml
index c0395011477..55a6a84a426 100644
--- a/modules/activiti-engine/src/main/resources/org/activiti/db/mapping/entity/HistoricTaskInstance.xml
+++ b/modules/activiti-engine/src/main/resources/org/activiti/db/mapping/entity/HistoricTaskInstance.xml
@@ -265,6 +265,10 @@
     select * from ${prefix}ACT_HI_TASKINST where ID_ = #{historicTaskInstanceId, jdbcType=VARCHAR}
   </select>
   
+  <select id="selectHistoricTasksByParentTaskId" parameterType="org.activiti.engine.impl.db.ListQueryParameterObject" resultMap="historicTaskInstanceResultMap">
+    select * from ${prefix}ACT_HI_TASKINST where PARENT_TASK_ID_ = #{parameter}
+  </select>
+  
   <select id="selectHistoricTaskInstanceIdsByProcessInstanceId" resultType="string" parameterType="org.activiti.engine.impl.db.ListQueryParameterObject" >
     select ID_ 
     from ${prefix}ACT_HI_TASKINST 
diff --git a/modules/activiti-engine/src/test/java/org/activiti/engine/test/api/task/SubTaskTest.java b/modules/activiti-engine/src/test/java/org/activiti/engine/test/api/task/SubTaskTest.java
index b7a91e766dd..12c2920cf8d 100644
--- a/modules/activiti-engine/src/test/java/org/activiti/engine/test/api/task/SubTaskTest.java
+++ b/modules/activiti-engine/src/test/java/org/activiti/engine/test/api/task/SubTaskTest.java
@@ -20,6 +20,8 @@
 import org.activiti.engine.history.HistoricTaskInstance;
 import org.activiti.engine.impl.history.HistoryLevel;
 import org.activiti.engine.impl.test.PluggableActivitiTestCase;
+import org.activiti.engine.repository.Deployment;
+import org.activiti.engine.runtime.ProcessInstance;
 import org.activiti.engine.task.Task;
 
 
@@ -80,4 +82,44 @@ public void testSubTask() {
 
     taskService.deleteTask(gonzoTaskId, true);
   }
+  
+  public void testSubTaskDeleteOnProcessInstanceDelete() {
+    Deployment deployment = repositoryService.createDeployment()
+        .addClasspathResource("org/activiti/engine/test/api/runtime/oneTaskProcess.bpmn20.xml")
+        .deploy();
+    
+    ProcessInstance processInstance = runtimeService.startProcessInstanceByKey("oneTaskProcess");
+    Task task = taskService.createTaskQuery().processInstanceId(processInstance.getId()).singleResult();
+    taskService.setAssignee(task.getId(), "test");
+    
+    Task subTask1 = taskService.newTask();
+    subTask1.setName("Sub task 1");
+    subTask1.setParentTaskId(task.getId());
+    subTask1.setAssignee("test");
+    taskService.saveTask(subTask1);
+    
+    Task subTask2 = taskService.newTask();
+    subTask2.setName("Sub task 2");
+    subTask2.setParentTaskId(task.getId());
+    subTask2.setAssignee("test");
+    taskService.saveTask(subTask2);
+    
+    List<Task> tasks = taskService.createTaskQuery().taskAssignee("test").list();
+    assertEquals(3, tasks.size());
+    
+    runtimeService.deleteProcessInstance(processInstance.getId(), "none");
+    
+    tasks = taskService.createTaskQuery().taskAssignee("test").list();
+    assertEquals(0, tasks.size());
+    
+    List<HistoricTaskInstance> historicTasks = historyService.createHistoricTaskInstanceQuery().taskAssignee("test").list();
+    assertEquals(3, historicTasks.size());
+    
+    historyService.deleteHistoricProcessInstance(processInstance.getId());
+    
+    historicTasks = historyService.createHistoricTaskInstanceQuery().taskAssignee("test").list();
+    assertEquals(0, historicTasks.size());
+    
+    repositoryService.deleteDeployment(deployment.getId(), true);
+  }
 }