diff --git a/packages/grpc-js/src/server.ts b/packages/grpc-js/src/server.ts
index 0d92881b..e6d17619 100644
--- a/packages/grpc-js/src/server.ts
+++ b/packages/grpc-js/src/server.ts
@@ -374,7 +374,11 @@ export class Server {
           }
         } catch (err) {
           const call = new Http2ServerCallStream(stream, null!);
-          err.code = Status.INTERNAL;
+
+          if (err.code === undefined) {
+            err.code = Status.INTERNAL;
+          }
+
           call.sendError(err);
         }
       }