diff --git a/graphene_mongo/converter.py b/graphene_mongo/converter.py
index 34ce6c88..e30c90d8 100644
--- a/graphene_mongo/converter.py
+++ b/graphene_mongo/converter.py
@@ -38,7 +38,7 @@ def convert_field_to_int(field, registry=None):
 
 @convert_mongoengine_field.register(mongoengine.BooleanField)
 def convert_field_to_boolean(field, registry=None):
-    return NonNull(Boolean, description=field.db_field)
+    return Boolean(description=field.db_field, required=not field.null)
 
 
 @convert_mongoengine_field.register(mongoengine.DecimalField)
diff --git a/graphene_mongo/tests/test_converter.py b/graphene_mongo/tests/test_converter.py
index 80394421..f770990f 100644
--- a/graphene_mongo/tests/test_converter.py
+++ b/graphene_mongo/tests/test_converter.py
@@ -58,8 +58,8 @@ def test_should_object_id_convert_id():
     assert_conversion(mongoengine.ObjectIdField, graphene.ID)
 
 
-def test_should_boolean_convert_non_null():
-    assert_conversion(mongoengine.BooleanField, graphene.NonNull)
+def test_should_boolean_convert_boolean():
+    assert_conversion(mongoengine.BooleanField, graphene.Boolean)
 
 
 def test_should_decimal_convert_float():