Abstract: Airborne electronic equipments have the requirements of light weight and high power density, and in fact, they need to face up to various severe mechanical environments during whole service lifetime. In this paper, weight-reduction design is conducted for the power supply assembly in airborne radar from modular and holistic level. In order to verify that the structure of the power supply assembly satisfies the strength and stiff-ness requirements, ANSYS software is used to analyze the mechanical response of the power supply assembly under the working conditions of acceleration overload, impact and random vibration. It could be concluded that the mechanical design of the power supply assembly satisfied the airborne environment requirements. The weight-reduction design and mechanical simulation analysis for the power supply assembly in this paper are helpful for guiding the mechanical design of other airborne electronic equipment.