diff --git a/src/transformers/models/longformer/modeling_tf_longformer.py b/src/transformers/models/longformer/modeling_tf_longformer.py
index bb193fbf638..dfe620ffb69 100644
--- a/src/transformers/models/longformer/modeling_tf_longformer.py
+++ b/src/transformers/models/longformer/modeling_tf_longformer.py
@@ -2082,6 +2082,7 @@ class TFLongformerForMaskedLM(TFLongformerPreTrainedModel, TFMaskedLanguageModel
         checkpoint=_CHECKPOINT_FOR_DOC,
         output_type=TFLongformerMaskedLMOutput,
         config_class=_CONFIG_FOR_DOC,
+        mask="<mask>",
     )
     def call(
         self,