Abstract: To simplify the preliminary proceedure of the finite element method, discretization of curved surface, in stress or strain analysis of a cylindrical shell with hole, the trans-formation of a cylindrical surface into a plane, so as to make the discretization easier, is carried out. After the discrelization of the surface, for saving time from calculating the coordinates of the Joints of the elementary triangles, the method of secondary auxiliary projection is used. As this solution has the advantage of visualization, it is easy to find out the error in calculating.