The embodiments of the present disclosure provide a method for processing 3D data, an apparatus for processing 3D data, a device and a storage medium. The method includes: acquiring three-dimensional point cloud data to be processed; mapping the three-dimensional point cloud data into a two-dimensional image space to obtain a first depth map; performing an expansion processing on the first depth map after changing an occlusion relation between target objects contained in the first depth map; and changing the occlusion relation between the target objects contained in the first depth map subject to the expansion processing to obtain a second depth map matched to the three-dimensional point cloud data.