diff --git a/paddlespeech/audio/utils/tensor_utils.py b/paddlespeech/audio/utils/tensor_utils.py
index b2436a121c53bc59cee60a5f129eaedd5413b1a7..93883c94dc3e25dc7a212ca35d15d98b785bcc1b 100644
--- a/paddlespeech/audio/utils/tensor_utils.py
+++ b/paddlespeech/audio/utils/tensor_utils.py
@@ -152,8 +152,8 @@ def add_sos_eos(ys_pad: paddle.Tensor, sos: int, eos: int,
     # return pad_sequence(ys_in, padding_value=eos).transpose([1,0]), pad_sequence(ys_out, padding_value=ignore_id).transpose([1,0])
 
     B = ys_pad.shape[0]
-    _sos = paddle.ones([B, 1], dtype=ys_pad.dtype) * sos
-    _eos = paddle.ones([B, 1], dtype=ys_pad.dtype) * eos
+    _sos = paddle.full([B, 1], sos, dtype=ys_pad.dtype)
+    _eos = paddle.full([B, 1], eos, dtype=ys_pad.dtype)
     ys_in = paddle.cat([_sos, ys_pad], dim=1)
     mask_pad = (ys_in == ignore_id)
     ys_in = ys_in.masked_fill(mask_pad, eos)