diff --git a/paddlespeech/t2s/frontend/tone_sandhi.py b/paddlespeech/t2s/frontend/tone_sandhi.py
index a46edf878..d8ea1a533 100644
--- a/paddlespeech/t2s/frontend/tone_sandhi.py
+++ b/paddlespeech/t2s/frontend/tone_sandhi.py
@@ -157,7 +157,7 @@ class ToneSandhi():
 
     def _split_word(self, word: str) -> List[str]:
         if len(word) == 3 and word[
-                -1:] == '子':  # three chars, like 老头子,the second char tone should not be 5 
+                -1:] == '子':   # three chars, like 老头子,the second char tone should not be 5 
             return [word]
         word_list = jieba.cut_for_search(word)
         word_list = sorted(word_list, key=lambda i: len(i), reverse=False)