diff --git a/mmcv/ops/csrc/parrots/cudabind.cpp b/mmcv/ops/csrc/parrots/cudabind.cpp
index 9627e26f4f..4521ddf4a9 100644
--- a/mmcv/ops/csrc/parrots/cudabind.cpp
+++ b/mmcv/ops/csrc/parrots/cudabind.cpp
@@ -564,57 +564,6 @@ REGISTER_DEVICE_IMPL(group_points_forward_impl, CUDA,
 REGISTER_DEVICE_IMPL(group_points_backward_impl, CUDA,
                      group_points_backward_cuda);
 
-void IoU3DBoxesOverlapBevForwardCUDAKernelLauncher(const int num_a,
-                                                   const Tensor boxes_a,
-                                                   const int num_b,
-                                                   const Tensor boxes_b,
-                                                   Tensor ans_overlap);
-
-void IoU3DNMS3DForwardCUDAKernelLauncher(const Tensor boxes, Tensor& keep,
-                                         Tensor& keep_num,
-                                         float nms_overlap_thresh);
-
-void IoU3DNMS3DNormalForwardCUDAKernelLauncher(const Tensor boxes, Tensor& keep,
-                                               Tensor& keep_num,
-                                               float nms_overlap_thresh);
-
-void iou3d_boxes_overlap_bev_forward_cuda(const int num_a, const Tensor boxes_a,
-                                          const int num_b, const Tensor boxes_b,
-                                          Tensor ans_overlap) {
-  IoU3DBoxesOverlapBevForwardCUDAKernelLauncher(num_a, boxes_a, num_b, boxes_b,
-                                                ans_overlap);
-};
-
-void iou3d_nms3d_forward_cuda(const Tensor boxes, Tensor& keep,
-                              Tensor& keep_num, float nms_overlap_thresh) {
-  IoU3DNMS3DForwardCUDAKernelLauncher(boxes, keep, keep_num,
-                                      nms_overlap_thresh);
-};
-
-void iou3d_nms3d_normal_forward_cuda(const Tensor boxes, Tensor& keep,
-                                     Tensor& keep_num,
-                                     float nms_overlap_thresh) {
-  IoU3DNMS3DNormalForwardCUDAKernelLauncher(boxes, keep, keep_num,
-                                            nms_overlap_thresh);
-};
-
-void iou3d_boxes_overlap_bev_forward_impl(const int num_a, const Tensor boxes_a,
-                                          const int num_b, const Tensor boxes_b,
-                                          Tensor ans_overlap);
-
-void iou3d_nms3d_forward_impl(const Tensor boxes, Tensor& keep,
-                              Tensor& keep_num, float nms_overlap_thresh);
-
-void iou3d_nms3d_normal_forward_impl(const Tensor boxes, Tensor& keep,
-                                     Tensor& keep_num,
-                                     float nms_overlap_thresh);
-
-REGISTER_DEVICE_IMPL(iou3d_boxes_overlap_bev_forward_impl, CUDA,
-                     iou3d_boxes_overlap_bev_forward_cuda);
-REGISTER_DEVICE_IMPL(iou3d_nms3d_forward_impl, CUDA, iou3d_nms3d_forward_cuda);
-REGISTER_DEVICE_IMPL(iou3d_nms3d_normal_forward_impl, CUDA,
-                     iou3d_nms3d_normal_forward_cuda);
-
 void KNNForwardCUDAKernelLauncher(int b, int n, int m, int nsample,
                                   const Tensor xyz, const Tensor new_xyz,
                                   Tensor idx, Tensor dist2);
diff --git a/setup.py b/setup.py
index 98ba6514bc..97720bcdbf 100644
--- a/setup.py
+++ b/setup.py
@@ -211,6 +211,7 @@ def get_extensions():
         op_files = glob.glob('./mmcv/ops/csrc/pytorch/cuda/*.cu') +\
             glob.glob('./mmcv/ops/csrc/pytorch/cpu/*.cpp') +\
             glob.glob('./mmcv/ops/csrc/parrots/*.cpp')
+        op_files.remove('./mmcv/ops/csrc/pytorch/cuda/iou3d_cuda.cu')
         include_dirs.append(os.path.abspath('./mmcv/ops/csrc/common'))
         include_dirs.append(os.path.abspath('./mmcv/ops/csrc/common/cuda'))
         cuda_args = os.getenv('MMCV_CUDA_ARGS')