diff --git a/single_view_recon/src/model/data_loader.py b/single_view_recon/src/model/data_loader.py
index 89f5e69..3357823 100644
--- a/single_view_recon/src/model/data_loader.py
+++ b/single_view_recon/src/model/data_loader.py
@@ -124,9 +124,9 @@ def get_batched_data(file_list, indices, sdf_dir, img_dir, cam_dir, point_num, t
             file = file_list[index]
             cat = file.split('/')[0]
             fn = file.split('/')[1]
-            sdf_dir_cat = sdf_dir + cat
-            img_dir_cat = img_dir + cat
-            cam_dir_cat = cam_dir + cat
+            sdf_dir_cat = os.path.join(sdf_dir, cat)
+            img_dir_cat = os.path.join(img_dir, cat)
+            cam_dir_cat = os.path.join(cam_dir, cat)
 
             # load the pre-defined SDF tfrecord
             sdf_file = os.path.join(sdf_dir_cat, fn + '.tfrecord')