A point cloud data encoding method is provided, which includes: acquiring initial point cloud data in a point cloud data processing environment; determining a space grid structure corresponding to the initial point cloud data; determining a filling order of different point cloud points in the initial point cloud data in the space grid structure; determining, based on the filling order of different point cloud points in the initial point cloud data in the space grid structure, residual information matched with the initial point cloud data; and encoding, according to the residual information, the initial point cloud data to obtain target point cloud data. A point cloud data decoding method, a point cloud data processing method, apparatuses, an electronic device, a computer program product, and a computer-readable storage medium are also provided.