The strategy of parametric design and the choice of development tools are introduced

and the output plate of the planetary bevel-type continuously variable transmission（CVT）as example

the process of parametric design system development of the CVT is introduced

including the design of system project and system program.In the design of system program

the detail of utilizing object process is introduced

defining the dimension variable of parts

the design of parametric program of parts

the link of the data base of standard parts

the design of the browse of 2D figures and 3D models

the design of the property modification program of parts

etc.and finally achieved the parametric design of the planetary bevel-type CVT

the designers could reduce repeated work and improve work efficiency by using the parametric design system.