Abstract: Based on SolidWorks software, a general parametric design method for 3D modeling of involute helical gear is proposed. This method uses the basic function of SolidWorks software to set 19 global variables, and then creates the profile and the path respectively by using the equation driven curves. Through swept cut and circular pattern, the 3D accurate model of the involute helical gear is finally obtained. (Not only the exact surface of the involute part, but also the exact surface of the root transition part are obtained.) The expressions of base circle groove width half angle, base circle radius, lead and pressure angle of initial point of an involute curve are derived. This method has the advantages of simple, fast, high precision and convenient modification, which lays a foundation for the rapid design of mechanical products.