Satellite laser retro-reflector (LRR) is a kind of ultra-precise optical component and its work environment is the blight space condition,so the mechanical design of LRR is of important significance for its proper function.In the paper,the mechanical configuration and design of the Galileo LRR is presented and expounded.Emphasis is focused on the environment adaptability and the influence of the stresses.Experiment results and conclusion are also given out.