diff --git a/ppdet/modeling/ops.py b/ppdet/modeling/ops.py
index 593d8dd375df134019ff8b86e3390d631f7e92f1..3ba07f5cb935982f963d2ab50305f00f7d0682c6 100644
--- a/ppdet/modeling/ops.py
+++ b/ppdet/modeling/ops.py
@@ -473,7 +473,7 @@ def distribute_fpn_proposals(fpn_rois,
                              pixel_offset=False,
                              rois_num=None,
                              name=None):
-    """
+    r"""
     
     **This op only takes LoDTensor as input.** In Feature Pyramid Networks 
     (FPN) models, it is needed to distribute all proposals into different FPN 
@@ -1274,7 +1274,7 @@ def box_coder(prior_box,
               box_normalized=True,
               axis=0,
               name=None):
-    """
+    r"""
     **Box Coder Layer**
     Encode/Decode the target bounding box with the priorbox information.