Abstract: In the process of stereolithography(SL),layers of liquid resin are successively cured by UV laser until the model's final shape is obtained.In the growth process,which is from dot to trace,from trace to area,and from 2D to 3D,a large number of vector scanning must be carried out,consequently,reasonable scanning paths can increase the productivity and the service life of the scanner.In this paper,a laser scanning path generating algorithm is proposed,which is well used in our SL machine.