Today, development and diversification for Computer Graphics have been making the modeling of complicated shape objects easy. A parametric surface is one of the representative method of objects,and can change the shape globally and express smoothing surface only a little number of control points. However, if point cloud data obtained from a 3D scanner are transformed into a parametric surface directly, its amount of data is very huge. therefore, the parametric surface's feature can never be utilized.

In this research, we propose the method which deletes control points of a parametric surface which has huge data volume and minimize errors for original surface, and the effective surface generation method using control points after deletion.