The parameterized geometric model of gear of helical gear limited slip differential is built by using CATIA software,which can modification quickly according to the input parameters that improved the design quality and efficiency greatly. After simplifying the geometric model of gears,its meshing contact analysis is carried out by using the finite element analysis method. The results show that the surface contact stress of design gear is far less than the material allowable contact stress,so gears won’t appear the contact fatigue damage,and the maximum bending stress position at gear root,and that is consistent with the actual situation and the maximum bending stress is less than the material allowable bending stress,so the design meets the requirements.