diff --git a/escheduler-api/src/main/java/cn/escheduler/api/service/ProcessInstanceService.java b/escheduler-api/src/main/java/cn/escheduler/api/service/ProcessInstanceService.java
index 9ba29e0555..f5f05a74d6 100644
--- a/escheduler-api/src/main/java/cn/escheduler/api/service/ProcessInstanceService.java
+++ b/escheduler-api/src/main/java/cn/escheduler/api/service/ProcessInstanceService.java
@@ -115,12 +115,18 @@ public class ProcessInstanceService extends BaseDAGService {
             return checkResult;
         }
         ProcessInstance processInstance = processDao.findProcessInstanceDetailById(processId);
+        String workerGroupName = "";
         if(processInstance.getWorkerGroupId() == -1){
-            processInstance.setWorkerGroupName(DEFAULT);
+            workerGroupName = DEFAULT;
         }else{
             WorkerGroup workerGroup = workerGroupMapper.queryById(processInstance.getWorkerGroupId());
-            processInstance.setWorkerGroupName(workerGroup.getName());
+            if(workerGroup != null){
+                workerGroupName = DEFAULT;
+            }else{
+                workerGroupName = workerGroup.getName();
+            }
         }
+        processInstance.setWorkerGroupName(workerGroupName);
         ProcessDefinition processDefinition = processDao.findProcessDefineById(processInstance.getProcessDefinitionId());
         processInstance.setReceivers(processDefinition.getReceivers());
         processInstance.setReceiversCc(processDefinition.getReceiversCc());
diff --git a/escheduler-dao/src/main/java/cn/escheduler/dao/ProcessDao.java b/escheduler-dao/src/main/java/cn/escheduler/dao/ProcessDao.java
index 8ba0f47960..d393339a5e 100644
--- a/escheduler-dao/src/main/java/cn/escheduler/dao/ProcessDao.java
+++ b/escheduler-dao/src/main/java/cn/escheduler/dao/ProcessDao.java
@@ -493,7 +493,8 @@ public class ProcessDao extends AbstractBaseDao {
         processInstance.setProcessInstanceJson(processDefinition.getProcessDefinitionJson());
         // set process instance priority
         processInstance.setProcessInstancePriority(command.getProcessInstancePriority());
-        processInstance.setWorkerGroupId(command.getWorkerGroupId());
+        int workerGroupId = command.getWorkerGroupId() == 0 ? -1 : command.getWorkerGroupId();
+        processInstance.setWorkerGroupId(workerGroupId);
         processInstance.setTimeout(processDefinition.getTimeout());
         processInstance.setTenantId(processDefinition.getTenantId());
         return processInstance;