diff --git a/chainercv/transforms/image/scale.py b/chainercv/transforms/image/scale.py
index 32b1c13a7c..84e91ca25d 100644
--- a/chainercv/transforms/image/scale.py
+++ b/chainercv/transforms/image/scale.py
@@ -27,9 +27,9 @@ def scale(img, size, fit_short=True):
     _, H, W = img.shape
 
     # If resizing is not necessary, return the input as is.
-    if fit_short and (H <= W and H == size) or (W <= H and W == size):
+    if fit_short and ((H <= W and H == size) or (W <= H and W == size)):
         return img
-    if not fit_short and (H >= W and H == size) or (W >= H and W == size):
+    if not fit_short and ((H >= W and H == size) or (W >= H and W == size)):
         return img
 
     if fit_short:
diff --git a/tests/transforms_tests/image_tests/test_scale.py b/tests/transforms_tests/image_tests/test_scale.py
index c0c9e3e3cb..3f160e3db4 100644
--- a/tests/transforms_tests/image_tests/test_scale.py
+++ b/tests/transforms_tests/image_tests/test_scale.py
@@ -11,10 +11,14 @@
      'fit_short': True, 'out_shape': (3, 12, 8)},
     {'in_shape': (3, 16, 24), 'size': 8,
      'fit_short': True, 'out_shape': (3, 8, 12)},
+    {'in_shape': (3, 16, 24), 'size': 24,
+     'fit_short': True, 'out_shape': (3, 24, 36)},
     {'in_shape': (3, 24, 16), 'size': 36,
      'fit_short': False, 'out_shape': (3, 36, 24)},
     {'in_shape': (3, 16, 24), 'size': 36,
      'fit_short': False, 'out_shape': (3, 24, 36)},
+    {'in_shape': (3, 24, 12), 'size': 12,
+     'fit_short': False, 'out_shape': (3, 12, 6)},
     # grayscale
     {'in_shape': (1, 16, 24), 'size': 8,
      'fit_short': True, 'out_shape': (1, 8, 12)},