diff --git a/configs/ssd/ssd_vgg16_300.yml b/configs/ssd/ssd_vgg16_300.yml
index a3266d87913bd3b253afa00870b328c20c136a81..fed09072dbf03ad6517c2e59f16720bf54f36598 100644
--- a/configs/ssd/ssd_vgg16_300.yml
+++ b/configs/ssd/ssd_vgg16_300.yml
@@ -100,7 +100,7 @@ TrainReader:
 EvalReader:
   inputs_def:
     image_shape: [3, 300, 300]
-    fields: ['image', 'gt_bbox', 'gt_class', 'im_shape', 'im_id', 'is_difficult']
+    fields: ['image', 'gt_bbox', 'gt_class', 'im_shape', 'im_id']
   dataset:
     !COCODataSet
     image_dir: val2017
diff --git a/configs/ssd/ssd_vgg16_512.yml b/configs/ssd/ssd_vgg16_512.yml
index 9e037cc2df545381378280d950d221123dc8d44e..1383acf4253383524c6e792ee0a366e5d9dbc56d 100644
--- a/configs/ssd/ssd_vgg16_512.yml
+++ b/configs/ssd/ssd_vgg16_512.yml
@@ -102,7 +102,7 @@ TrainReader:
 EvalReader:
   inputs_def:
     image_shape: [3,512,512]
-    fields: ['image', 'gt_bbox', 'gt_class', 'im_shape', 'im_id', 'is_difficult']
+    fields: ['image', 'gt_bbox', 'gt_class', 'im_shape', 'im_id']
   dataset:
     !COCODataSet
     image_dir: val2017