diff --git a/mmedit/datasets/base_sr_dataset.py b/mmedit/datasets/base_sr_dataset.py
index 0736d1b3da..6e81150560 100644
--- a/mmedit/datasets/base_sr_dataset.py
+++ b/mmedit/datasets/base_sr_dataset.py
@@ -9,7 +9,7 @@
 from .base_dataset import BaseDataset
 
 IMG_EXTENSIONS = ('.jpg', '.JPG', '.jpeg', '.JPEG', '.png', '.PNG', '.ppm',
-                  '.PPM', '.bmp', '.BMP')
+                  '.PPM', '.bmp', '.BMP', '.tif', '.TIF', '.tiff', '.TIFF')
 
 
 class BaseSRDataset(BaseDataset):