diff --git a/OpenAuth.App/FlowApproverApp/FlowApproverApp.cs b/OpenAuth.App/FlowApproverApp/FlowApproverApp.cs
index fcc5a59a..8d27ee52 100644
--- a/OpenAuth.App/FlowApproverApp/FlowApproverApp.cs
+++ b/OpenAuth.App/FlowApproverApp/FlowApproverApp.cs
@@ -78,6 +78,10 @@ namespace OpenAuth.App
         public string[] GetApproverIds(QueryApproverReq req)
         {
             var approvers = GetApprovers(req);
+            if (approvers == null)
+            {
+                return Array.Empty<string>();
+            }
             //否则并行且/并行或都是返回所有加签人
             return approvers.Select(u => u.ApproverId).ToArray();
         }
diff --git a/OpenAuth.App/FlowInstance/FlowInstanceApp.cs b/OpenAuth.App/FlowInstance/FlowInstanceApp.cs
index 393d87a0..854ddc13 100644
--- a/OpenAuth.App/FlowInstance/FlowInstanceApp.cs
+++ b/OpenAuth.App/FlowInstance/FlowInstanceApp.cs
@@ -422,7 +422,7 @@ namespace OpenAuth.App
                     ActivityId = flowInstance.ActivityId
                 });
 
-                var approverInfo = approvers.Find(u => u.ApproverId == user.Id);
+                var approverInfo = approvers?.Find(u => u.ApproverId == user.Id);
                 if (approverInfo != null)
                 {
                     //如果是加签，则调整加签状态