diff --git a/src/transformers/configuration_reformer.py b/src/transformers/configuration_reformer.py
index 8d364680664..7532684fddb 100755
--- a/src/transformers/configuration_reformer.py
+++ b/src/transformers/configuration_reformer.py
@@ -115,6 +115,8 @@ class ReformerConfig(PretrainedConfig):
         vocab_size (:obj:`int`, optional, defaults to 320):
             Vocabulary size of the Reformer model. Defines the different tokens that
             can be represented by the `inputs_ids` passed to the forward method of :class:`~transformers.ReformerModel`.
+        tie_word_embeddings (:obj:`bool`, `optional`, defaults to :obj:`False`):
+            Whether to tie input and output embeddings.
 
     Example::