diff --git a/ruby/src/main/java/com/google/protobuf/jruby/RubyFieldDescriptor.java b/ruby/src/main/java/com/google/protobuf/jruby/RubyFieldDescriptor.java
index 6f52e1006785..189d881fbc25 100644
--- a/ruby/src/main/java/com/google/protobuf/jruby/RubyFieldDescriptor.java
+++ b/ruby/src/main/java/com/google/protobuf/jruby/RubyFieldDescriptor.java
@@ -287,6 +287,8 @@ protected FieldDescriptor getDescriptor() {
   private void calculateLabel(ThreadContext context) {
     if (descriptor.isRepeated()) {
       this.label = context.runtime.newSymbol("repeated");
+    } else if (descriptor.isRequired()) {
+      this.label = context.runtime.newSymbol("required");
     } else if (descriptor.isOptional()) {
       this.label = context.runtime.newSymbol("optional");
     } else {