diff --git a/mmrotate/core/bbox/iou_calculators/rotate_iou2d_calculator.py b/mmrotate/core/bbox/iou_calculators/rotate_iou2d_calculator.py
index 7e40e41ab..3c84c6e14 100644
--- a/mmrotate/core/bbox/iou_calculators/rotate_iou2d_calculator.py
+++ b/mmrotate/core/bbox/iou_calculators/rotate_iou2d_calculator.py
@@ -35,6 +35,7 @@ def __call__(self,
         """
         assert bboxes1.size(-1) in [0, 5, 6]
         assert bboxes2.size(-1) in [0, 5, 6]
+
         if bboxes2.size(-1) == 6:
             bboxes2 = bboxes2[..., :5]
         if bboxes1.size(-1) == 6:
@@ -69,6 +70,10 @@ def rbbox_overlaps(bboxes1, bboxes2, mode='iou', is_aligned=False):
     assert (bboxes1.size(-1) == 5 or bboxes1.size(0) == 0)
     assert (bboxes2.size(-1) == 5 or bboxes2.size(0) == 0)
 
+    # resolve `rbbox_overlaps` abnormal when input rbbox is too small.
+    bboxes1[2:4].clamp_(min=1e-3)
+    bboxes2[2:4].clamp_(min=1e-3)
+
     rows = bboxes1.size(0)
     cols = bboxes2.size(0)
     if is_aligned:
diff --git a/tests/test_utils/test_overlaps.py b/tests/test_utils/test_overlaps.py
new file mode 100644
index 000000000..9d6586438
--- /dev/null
+++ b/tests/test_utils/test_overlaps.py
@@ -0,0 +1,32 @@
+# Copyright (c) OpenMMLab. All rights reserved.
+import pytest
+import torch
+
+from mmrotate.core.bbox import rbbox_overlaps
+
+predict = [[903.34, 1034.4, 1.81e-7, 1e-7, -0.312],
+           [903.34, 1034.4, 1e-7, 1e-3, -0.312],
+           [903.34, 1034.4, 1.81e7, 1e7, -0.312]]
+gt = [[2.1525e+02, 7.5750e+01, 3.3204e+01, 1.2649e+01, 3.2175e-01],
+      [3.0013e+02, 7.7144e+02, 4.9222e+02, 3.1368e+02, -1.3978e+00],
+      [8.4887e+02, 6.9989e+02, 4.6854e+02, 3.0743e+02, -1.4008e+00],
+      [8.5250e+02, 7.0250e+02, 7.6181e+02, 3.8200e+02, -1.3984e+00]]
+expect_ious = [[0., 0., 0., 0.], [0., 0., 0., 0.], [0., 0., 0., 0.]]
+
+
+def test_rbbox_overlaps_cpu():
+    predict_tensor = torch.tensor(predict)
+    gt_tensor = torch.tensor(gt)
+    expect_ious_tensor = torch.tensor(expect_ious)
+    ious = rbbox_overlaps(predict_tensor, gt_tensor)
+    torch.allclose(ious, expect_ious_tensor, atol=1e-3)
+
+
+@pytest.mark.skipif(
+    not torch.cuda.is_available(), reason='requires CUDA support')
+def test_rbbox_overlaps_cuda():
+    predict_tensor = torch.tensor(predict, device='cuda')
+    gt_tensor = torch.tensor(gt, device='cuda')
+    expect_ious_tensor = torch.tensor(expect_ious, device='cuda')
+    ious = rbbox_overlaps(predict_tensor, gt_tensor)
+    torch.allclose(ious, expect_ious_tensor, atol=1e-3)