diff --git a/paddlespeech/s2t/modules/encoder.py b/paddlespeech/s2t/modules/encoder.py
index abdaf5ea7d6507336e8459b288cb3b9ffb6a88fb..cf4e32fa486c8cb6617997cde2f25c67dbdea839 100644
--- a/paddlespeech/s2t/modules/encoder.py
+++ b/paddlespeech/s2t/modules/encoder.py
@@ -255,6 +255,7 @@ class BaseEncoder(nn.Layer):
                 xs,
                 att_mask,
                 pos_emb,
+                mask_pad=paddle.ones([0, 0, 0], dtype=paddle.bool),
                 att_cache=att_cache[i:i + 1] if elayers > 0 else att_cache,
                 cnn_cache=cnn_cache[i:i + 1]
                 if paddle.shape(cnn_cache)[0] > 0 else cnn_cache, )
diff --git a/paddlespeech/s2t/modules/encoder_layer.py b/paddlespeech/s2t/modules/encoder_layer.py
index 3972ff90afea244b3f82fa86c4166ad5c4639565..4555b535f7bd76b529b4fd397438d5f1579b2928 100644
--- a/paddlespeech/s2t/modules/encoder_layer.py
+++ b/paddlespeech/s2t/modules/encoder_layer.py
@@ -195,8 +195,7 @@ class ConformerEncoderLayer(nn.Layer):
             x: paddle.Tensor,
             mask: paddle.Tensor,
             pos_emb: paddle.Tensor,
-            mask_pad: paddle.
-            Tensor,  # paddle.ones([0, 0, 0], dtype=paddle.bool)
+            mask_pad: paddle.Tensor,  #paddle.ones([0, 0, 0],dtype=paddle.bool)
             att_cache: paddle.Tensor,  # paddle.zeros([0, 0, 0, 0])
             cnn_cache: paddle.Tensor,  # paddle.zeros([0, 0, 0, 0])
     ) -> Tuple[paddle.Tensor, paddle.Tensor, paddle.Tensor, paddle.Tensor]:
diff --git a/paddlespeech/server/engine/asr/online/python/asr_engine.py b/paddlespeech/server/engine/asr/online/python/asr_engine.py
index 96d4823e27dccd980288e1ae98efae0333b74295..87d88ee602bc1ec7bc1af8fc96153926bc98045c 100644
--- a/paddlespeech/server/engine/asr/online/python/asr_engine.py
+++ b/paddlespeech/server/engine/asr/online/python/asr_engine.py
@@ -476,8 +476,12 @@ class PaddleASRConnectionHanddler:
             # forward chunk
             (y, self.att_cache,
              self.cnn_cache) = self.model.encoder.forward_chunk(
-                 chunk_xs, self.offset, required_cache_size, self.att_cache,
-                 self.cnn_cache, paddle.ones([0, 0, 0], dtype=paddle.bool))
+                 chunk_xs,
+                 self.offset,
+                 required_cache_size,
+                 att_cache=self.att_cache,
+                 cnn_cache=self.cnn_cache,
+                 att_mask=paddle.ones([0, 0, 0], dtype=paddle.bool))
             outputs.append(y)
 
             # update the global offset, in decoding frame unit