In a method for processing a point cloud using a computing device, a straight line fitted by the point cloud comprising border points is determined as a benchmark line. An inflection point in the point cloud of the benchmark line is determined. If the vertical distance of the inflection point is not greater than the preset filtration value, needless border points in the point cloud are deleted and a remainder point cloud is obtained. If the vertical distance between the inflection point and the benchmark line is greater than a filtration value, the point cloud is divided into two sub-point clouds, and the one sub-point cloud having border points less than the preset number is deleted, and the other sub-point cloud is set as a remainder point cloud.