diff --git a/ppdet/utils/coco_eval.py b/ppdet/utils/coco_eval.py
index c2c8597bacc05f976d6afdf946f0ea1d1397c7bc..f71f38ff4e0f28c03daf7026da2445999f3cebb5 100644
--- a/ppdet/utils/coco_eval.py
+++ b/ppdet/utils/coco_eval.py
@@ -82,7 +82,7 @@ def mask_eval(results, anno_file, outfile, resolution, thresh_binarize=0.5):
 
     segm_results = mask2out(results, clsid2catid, resolution, thresh_binarize)
     assert len(
-        segms_results) > 0, "The number of valid mask detected is zero.\n \
+        segm_results) > 0, "The number of valid mask detected is zero.\n \
         Please use reasonable model and check input data."
 
     with open(outfile, 'w') as f: