diff --git a/django_mailbox/models.py b/django_mailbox/models.py
index 3c7e785..fe99ce0 100644
--- a/django_mailbox/models.py
+++ b/django_mailbox/models.py
@@ -724,9 +724,7 @@ class MessageAttachment(models.Model):
         """Returns the original filename of this attachment."""
         file_name = self._get_rehydrated_headers().get_filename()
         if isinstance(file_name, six.text_type):
-            return file_name
-        elif file_name:
-            return convert_header_to_unicode(file_name)
+            return utils.convert_header_to_unicode(file_name)
         else:
             return None
 
diff --git a/django_mailbox/tests/test_process_email.py b/django_mailbox/tests/test_process_email.py
index e3d4778..8bb70c9 100644
--- a/django_mailbox/tests/test_process_email.py
+++ b/django_mailbox/tests/test_process_email.py
@@ -40,6 +40,31 @@ class TestProcessEmail(EmailMessageTestCase):
             'Adam Coddington <test@adamcoddington.net>',
         )
 
+    def test_message_with_encoded_attachment_filenames(self):
+        message = self._get_email_object(
+            'message_with_koi8r_filename_attachments.eml'
+        )
+
+        mailbox = Mailbox.objects.create()
+        msg = mailbox.process_incoming_message(message)
+
+        attachments = msg.attachments.order_by('pk').all()
+        self.assertEqual(
+            '\u041f\u0430\u043a\u0435\u0442 \u043f\u0440\u0435\u0434\u043b'
+            '\u043e\u0436\u0435\u043d\u0438\u0439 HSE Career Fair 8 \u0430'
+            '\u043f\u0440\u0435\u043b\u044f 2016.pdf',
+            attachments[0].get_filename()
+        )
+        self.assertEqual(
+            '\u0412\u0435\u0434\u043e\u043c\u043e\u0441\u0442\u0438.pdf',
+            attachments[1].get_filename()
+        )
+        self.assertEqual(
+            '\u041f\u0430\u043a\u0435\u0442 \u043f\u0440\u0435\u0434\u043b'
+            '\u043e\u0436\u0435\u043d\u0438\u0439 2016.pptx',
+            attachments[2].get_filename()
+        )
+
     def test_message_with_attachments(self):
         message = self._get_email_object('message_with_attachment.eml')