diff --git a/neo/Network/RPC/RpcServer.cs b/neo/Network/RPC/RpcServer.cs
index 9ba441c381..1dcce9f107 100644
--- a/neo/Network/RPC/RpcServer.cs
+++ b/neo/Network/RPC/RpcServer.cs
@@ -669,6 +669,14 @@ private JObject ProcessRequest(HttpContext context, JObject request)
                 if (result == null)
                     result = Process(method, _params);
             }
+            catch (FormatException)
+            {
+                return CreateErrorResponse(request["id"], -32602, "Invalid params");
+            }
+            catch (IndexOutOfRangeException)
+            {
+                return CreateErrorResponse(request["id"], -32602, "Invalid params");
+            }
             catch (Exception ex)
             {
 #if DEBUG