diff --git a/ppdet/modeling/transformers/deformable_transformer.py b/ppdet/modeling/transformers/deformable_transformer.py
index 0c2089a8b638838295d7f26efb48782a80cf6903..db07e0327df26a264b995645abfc3af9e1d1080d 100644
--- a/ppdet/modeling/transformers/deformable_transformer.py
+++ b/ppdet/modeling/transformers/deformable_transformer.py
@@ -448,7 +448,6 @@ class DeformableTransformer(nn.Layer):
         return {'backbone_num_channels': [i.channels for i in input_shape], }
 
     def _get_valid_ratio(self, mask):
-        mask = mask.astype(paddle.float32)
         _, H, W = mask.shape
         valid_ratio_h = paddle.sum(mask[:, :, 0], 1) / H
         valid_ratio_w = paddle.sum(mask[:, 0, :], 1) / W
@@ -477,18 +476,16 @@ class DeformableTransformer(nn.Layer):
             src = src.flatten(2).transpose([0, 2, 1])
             src_flatten.append(src)
             if src_mask is not None:
-                mask = F.interpolate(
-                    src_mask.unsqueeze(0).astype(src.dtype),
-                    size=(h, w))[0].astype('bool')
+                mask = F.interpolate(src_mask.unsqueeze(0), size=(h, w))[0]
             else:
-                mask = paddle.ones([bs, h, w], dtype='bool')
+                mask = paddle.ones([bs, h, w])
             valid_ratios.append(self._get_valid_ratio(mask))
             pos_embed = self.position_embedding(mask).flatten(2).transpose(
                 [0, 2, 1])
             lvl_pos_embed = pos_embed + self.level_embed.weight[level].reshape(
                 [1, 1, -1])
             lvl_pos_embed_flatten.append(lvl_pos_embed)
-            mask = mask.astype(src.dtype).flatten(1)
+            mask = mask.flatten(1)
             mask_flatten.append(mask)
         src_flatten = paddle.concat(src_flatten, 1)
         mask_flatten = paddle.concat(mask_flatten, 1)