diff --git a/rest_framework/utils/field_mapping.py b/rest_framework/utils/field_mapping.py
index dbd145371..ab42fc605 100644
--- a/rest_framework/utils/field_mapping.py
+++ b/rest_framework/utils/field_mapping.py
@@ -127,13 +127,13 @@ def get_field_kwargs(field_name, model_field):
     else:
         # Ensure that max_value is passed explicitly as a keyword arg,
         # rather than as a validator.
-        max_value, messsage = next((
+        max_value, message = next((
             (validator.limit_value, validator.message) for validator in validator_kwarg
             if isinstance(validator, validators.MaxValueValidator)
         ), (None, None))
         if max_value is not None and isinstance(model_field, NUMERIC_FIELD_TYPES):
             kwargs['max_value'] = max_value
-            kwargs['error_messages'] = {'max_value': messsage}
+            kwargs['error_messages'] = {'max_value': message}
             validator_kwarg = [
                 validator for validator in validator_kwarg
                 if not isinstance(validator, validators.MaxValueValidator)
@@ -141,13 +141,13 @@ def get_field_kwargs(field_name, model_field):
 
         # Ensure that min_value is passed explicitly as a keyword arg,
         # rather than as a validator.
-        min_value, messsage = next((
+        min_value, message = next((
             (validator.limit_value, validator.message) for validator in validator_kwarg
             if isinstance(validator, validators.MinValueValidator)
         ), (None, None))
         if min_value is not None and isinstance(model_field, NUMERIC_FIELD_TYPES):
             kwargs['min_value'] = min_value
-            kwargs['error_messages'] = {**kwargs['error_messages'], **{'min_value': messsage}}
+            kwargs.setdefault('error_messages', {}).update(min_value=message)
             validator_kwarg = [
                 validator for validator in validator_kwarg
                 if not isinstance(validator, validators.MinValueValidator)
diff --git a/tests/test_model_serializer.py b/tests/test_model_serializer.py
index af4f63ca2..814901331 100644
--- a/tests/test_model_serializer.py
+++ b/tests/test_model_serializer.py
@@ -214,6 +214,9 @@ class TestRegularFieldMappings(TestCase):
             expected = expected.replace(
                 "('red', 'Red'), ('blue', 'Blue'), ('green', 'Green')",
                 "(u'red', u'Red'), (u'blue', u'Blue'), (u'green', u'Green')"
+            ).replace(
+                "{'max_value': 'Ensure this value is less than or equal to %(limit_value)s.', 'min_value': 'Ensure this value is greater than or equal to %(limit_value)s.'}",
+                {'max_value': u'Ensure this value is less than or equal to %(limit_value)s.', 'min_value': u'Ensure this value is greater than or equal to %(limit_value)s.'}
             )
         self.assertEqual(unicode_repr(TestSerializer()), expected)