diff --git a/.flake8 b/.flake8
index c7c4f1855..7479828a5 100644
--- a/.flake8
+++ b/.flake8
@@ -10,6 +10,7 @@ per-file-ignores =
     egs/*/ASR/*/optim.py: E501,
     egs/*/ASR/*/scaling.py: E501,
     egs/librispeech/ASR/conv_emformer_transducer_stateless/*.py: E501, E203
+    egs/librispeech/ASR/lstm_transducer_stateless/*.py: E501, E203
 
     # invalid escape sequence (cause by tex formular), W605
     icefall/utils.py: E501, W605