The engine mount system is an important part of the vehicle, Play the role of supporting engine, blocking vibration and improving ride comfort in the process of driving This paper studies the relationship between the stiffness of the suspension element and the inherent characteristics of the suspension system by modeling and simulation of the automobile engine. In Adams software, a three-dimensional model of the engine suspension system is established, simulation analysis is conducted, and the intrinsic frequency and vibration modal energy decoupling distribution of the suspension system is obtained in the Vibration vibration module. The analysis shows that the vibration isolation effect is poor. With the stiffness of suspended rubber pad as the optimized parameter, a new energy decoupling distribution is obtained, and the decoupling rate in the main vibration direction reaches more than 80%. Compared with the initial data, the decoupling degree is greatly improved, which shows that the optimized data has obvious effect on the vibration isolation of the engine, and verifies the feasibility of the optimized design method.