diff --git a/fluid/neural_machine_translation/transformer/infer.py b/fluid/neural_machine_translation/transformer/infer.py
index 2338975f980e472224e599d83891f2b27f814ece..5634f160a99f83dd1b35e83251c303604f7e78a1 100644
--- a/fluid/neural_machine_translation/transformer/infer.py
+++ b/fluid/neural_machine_translation/transformer/infer.py
@@ -301,6 +301,9 @@ def main():
 
     trg_idx2word = paddle.dataset.wmt16.get_dict(
         "de", dict_size=ModelHyperParams.trg_vocab_size, reverse=True)
+    # Append the <pad> token since the dict provided by dataset.wmt16 does
+    # not include it.
+    trg_idx2word[ModelHyperParams.trg_pad_idx] = "<pad>"
 
     def post_process_seq(seq,
                          bos_idx=ModelHyperParams.bos_idx,