Abstract: Process of parametric modeling of bevel gear with standard evolute tooth on PC-based CAD system is presented.First the main body and teeth of bevel gear are constructed interactively on the CAD system and save the commands of construction process as a macro.After assigning new parameters to the macro and rerunning it,it would generate the shape of needed gear.In such a way,it is quite easy to realize the customization of common CAD software.