diff --git a/compiler/cpp/src/thrift/generate/t_csharp_generator.cc b/compiler/cpp/src/thrift/generate/t_csharp_generator.cc
index 62a3e57..10d28b2 100644
--- a/compiler/cpp/src/thrift/generate/t_csharp_generator.cc
+++ b/compiler/cpp/src/thrift/generate/t_csharp_generator.cc
@@ -2820,6 +2820,8 @@
       }
       if (ttype->is_base_type()) {
         use_nullable = ((t_base_type*)ttype)->get_base() != t_base_type::TYPE_STRING;
+      } else if (ttype->is_enum()) {
+        use_nullable = true;
       }
     }
     indent(out) << "return " << fieldPrefix + tfield->get_name() << ";" << endl;