Expansion joints are non-standard devices which shape and parameters could vary with temperature, pressure, displacement and cycle life. The drawing work of expansion joints is rather important. A set of accurate, reliable and strong practical professional graphics software is needed for expansion joint industry. On the basis of digestion and absorption of SolidWorks 2010, secondary development of the software was carried out in this paper so as to meet the urgent needs of expansion joints industry. The structures of most bellows expansion joints are not complex, and their geometries are relatively simple and fixed. It is very suitable for bellows expansion joints solved with parametric modeling method.