diff --git a/dolphinscheduler-api/src/main/java/org/apache/dolphinscheduler/api/service/ProcessDefinitionService.java b/dolphinscheduler-api/src/main/java/org/apache/dolphinscheduler/api/service/ProcessDefinitionService.java
index 2d462b3cac..5fe708ce8c 100644
--- a/dolphinscheduler-api/src/main/java/org/apache/dolphinscheduler/api/service/ProcessDefinitionService.java
+++ b/dolphinscheduler-api/src/main/java/org/apache/dolphinscheduler/api/service/ProcessDefinitionService.java
@@ -802,66 +802,68 @@ public class ProcessDefinitionService extends BaseDAGService {
                 JSONObject subParams = JSONUtils.parseObject(taskNode.getString("params"));
                 Integer subProcessId = subParams.getInteger("processDefinitionId");
                 ProcessDefinition subProcess = processDefineMapper.queryByDefineId(subProcessId);
-                String subProcessJson = subProcess.getProcessDefinitionJson();
-                //check current project has sub process
-                ProcessDefinition currentProjectSubProcess = processDefineMapper.queryByDefineName(targetProject.getId(), subProcess.getName());
-
-                if (null == currentProjectSubProcess) {
-                    JSONArray subJsonArray = (JSONArray) JSONUtils.parseObject(subProcess.getProcessDefinitionJson()).get("tasks");
-
-                    List<Object> subProcessList = subJsonArray.stream()
-                            .filter(item -> checkTaskHasSubProcess(JSONUtils.parseObject(item.toString()).getString("type")))
-                            .collect(Collectors.toList());
-
-                    if (CollectionUtils.isNotEmpty(subProcessList)) {
-                        importSubProcess(loginUser, targetProject, subJsonArray, subProcessIdMap);
-                        //sub process processId correct
-                        if (!subProcessIdMap.isEmpty()) {
-
-                            for (Map.Entry<Integer, Integer> entry : subProcessIdMap.entrySet()) {
-                                String oldSubProcessId = "\"processDefinitionId\":" + entry.getKey();
-                                String newSubProcessId = "\"processDefinitionId\":" + entry.getValue();
-                                subProcessJson = subProcessJson.replaceAll(oldSubProcessId, newSubProcessId);
+                //check is sub process exist in db
+                if (null != subProcess) {
+                    String subProcessJson = subProcess.getProcessDefinitionJson();
+                    //check current project has sub process
+                    ProcessDefinition currentProjectSubProcess = processDefineMapper.queryByDefineName(targetProject.getId(), subProcess.getName());
+
+                    if (null == currentProjectSubProcess) {
+                        JSONArray subJsonArray = (JSONArray) JSONUtils.parseObject(subProcess.getProcessDefinitionJson()).get("tasks");
+
+                        List<Object> subProcessList = subJsonArray.stream()
+                                .filter(item -> checkTaskHasSubProcess(JSONUtils.parseObject(item.toString()).getString("type")))
+                                .collect(Collectors.toList());
+
+                        if (CollectionUtils.isNotEmpty(subProcessList)) {
+                            importSubProcess(loginUser, targetProject, subJsonArray, subProcessIdMap);
+                            //sub process processId correct
+                            if (!subProcessIdMap.isEmpty()) {
+
+                                for (Map.Entry<Integer, Integer> entry : subProcessIdMap.entrySet()) {
+                                    String oldSubProcessId = "\"processDefinitionId\":" + entry.getKey();
+                                    String newSubProcessId = "\"processDefinitionId\":" + entry.getValue();
+                                    subProcessJson = subProcessJson.replaceAll(oldSubProcessId, newSubProcessId);
+                                }
+
+                                subProcessIdMap.clear();
                             }
-
-                            subProcessIdMap.clear();
                         }
-                    }
 
-                    //if sub-process recursion
-                    Date now = new Date();
-                    //create sub process in target project
-                    ProcessDefinition processDefine = new ProcessDefinition();
-                    processDefine.setName(subProcess.getName());
-                    processDefine.setVersion(subProcess.getVersion());
-                    processDefine.setReleaseState(subProcess.getReleaseState());
-                    processDefine.setProjectId(targetProject.getId());
-                    processDefine.setUserId(loginUser.getId());
-                    processDefine.setProcessDefinitionJson(subProcessJson);
-                    processDefine.setDescription(subProcess.getDescription());
-                    processDefine.setLocations(subProcess.getLocations());
-                    processDefine.setConnects(subProcess.getConnects());
-                    processDefine.setTimeout(subProcess.getTimeout());
-                    processDefine.setTenantId(subProcess.getTenantId());
-                    processDefine.setGlobalParams(subProcess.getGlobalParams());
-                    processDefine.setCreateTime(now);
-                    processDefine.setUpdateTime(now);
-                    processDefine.setFlag(subProcess.getFlag());
-                    processDefine.setReceivers(subProcess.getReceivers());
-                    processDefine.setReceiversCc(subProcess.getReceiversCc());
-                    processDefineMapper.insert(processDefine);
-
-                    logger.info("create sub process, project: {}, process name: {}", targetProject.getName(), processDefine.getName());
-
-                    //modify task node
-                    ProcessDefinition newSubProcessDefine = processDefineMapper.queryByDefineName(processDefine.getProjectId(),processDefine.getName());
-
-                    if (null != newSubProcessDefine) {
-                        subProcessIdMap.put(subProcessId, newSubProcessDefine.getId());
-                        subParams.put("processDefinitionId", newSubProcessDefine.getId());
-                        taskNode.put("params", subParams);
+                        //if sub-process recursion
+                        Date now = new Date();
+                        //create sub process in target project
+                        ProcessDefinition processDefine = new ProcessDefinition();
+                        processDefine.setName(subProcess.getName());
+                        processDefine.setVersion(subProcess.getVersion());
+                        processDefine.setReleaseState(subProcess.getReleaseState());
+                        processDefine.setProjectId(targetProject.getId());
+                        processDefine.setUserId(loginUser.getId());
+                        processDefine.setProcessDefinitionJson(subProcessJson);
+                        processDefine.setDescription(subProcess.getDescription());
+                        processDefine.setLocations(subProcess.getLocations());
+                        processDefine.setConnects(subProcess.getConnects());
+                        processDefine.setTimeout(subProcess.getTimeout());
+                        processDefine.setTenantId(subProcess.getTenantId());
+                        processDefine.setGlobalParams(subProcess.getGlobalParams());
+                        processDefine.setCreateTime(now);
+                        processDefine.setUpdateTime(now);
+                        processDefine.setFlag(subProcess.getFlag());
+                        processDefine.setReceivers(subProcess.getReceivers());
+                        processDefine.setReceiversCc(subProcess.getReceiversCc());
+                        processDefineMapper.insert(processDefine);
+
+                        logger.info("create sub process, project: {}, process name: {}", targetProject.getName(), processDefine.getName());
+
+                        //modify task node
+                        ProcessDefinition newSubProcessDefine = processDefineMapper.queryByDefineName(processDefine.getProjectId(),processDefine.getName());
+
+                        if (null != newSubProcessDefine) {
+                            subProcessIdMap.put(subProcessId, newSubProcessDefine.getId());
+                            subParams.put("processDefinitionId", newSubProcessDefine.getId());
+                            taskNode.put("params", subParams);
+                        }
                     }
-
                 }
             }
         }