Abstract: The Whiffle-tree type axial support mechanism is widely adopted by most relatively large optical mirrors. Based on the secondary developing tools offered by the commonly used Finite Element Analysis(FEA) software ANSYS, ANSYS Parametric Design Language(APDL) is used for creating the mirror FEA model driven by parameters, and ANSYS User Interface Design Language(UIDL) for generating custom menu of interactive manner, whereby, the relatively independent dedicated Computer Aided Engineering(CAE) module is embedded in ANSYS for calculation and optimization of axial Whiffle-tree support of optical mirrors. An example is also described to illustrate the intuitive and effective usage of the dedicated module by boosting work efficiency and releasing related engineering knowledge of user. The philosophy of secondary-developed special module with commonly used software also suggests itself for product development in other industries.