diff --git a/src/transformers/tokenization_blenderbot.py b/src/transformers/tokenization_blenderbot.py
index b5f0cefcbb99..d93962598851 100644
--- a/src/transformers/tokenization_blenderbot.py
+++ b/src/transformers/tokenization_blenderbot.py
@@ -134,7 +134,7 @@ def __init__(
         bos_token="__start__",
         eos_token="__end__",
         unk_token="__unk__",
-        pad_token="__null",
+        pad_token="__null__",
         **kwargs
     ):
         super().__init__(unk_token=unk_token, bos_token=bos_token, eos_token=eos_token, pad_token=pad_token, **kwargs)