1. A system for simplifying a mesh point cloud, the system including electronic computer hardware in combination with software, comprising: a point cloud data inputting module for obtaining a point cloud and processing the point cloud into a mesh point cloud including a plurality of triangular grids; a vector computing module for calculating a distance between each of vertexes of each triangular grid and its normal plane and determining influences of the vertexes to a geometric characteristic of the mesh point cloud, wherein vertexes which have longer distances with their corresponding normal planes have larger influences; a point deleting module for deleting points of the points and grids in connection with the points in accordance with a predetermined degree of simplification whereby at least a void part is formed in the mesh point cloud, wherein the deleted points are corresponding to the vertexes which have less influences to the geometric characteristic of the mesh point cloud; and a local meshing module for creating triangular grids to fill the at least a void part to form a new mesh point cloud.