diff --git a/pgl/math.py b/pgl/math.py
index 6e90795f..ce2e0b4e 100644
--- a/pgl/math.py
+++ b/pgl/math.py
@@ -23,10 +23,6 @@
 ]
 
 import paddle
-from paddle import _C_ops
-from paddle.common_ops_import import LayerHelper
-from paddle.common_ops_import import _non_static_mode
-from paddle.common_ops_import import check_variable_and_dtype
 from pgl.utils.op import get_index_from_counts