Based on the analysis of the belt misalignment of the metal V belt CVT, the reason of the belt misalignment has been discussed. In order to control the misalignment, an electro-hydraulic control system has been designed. After deeply analyzing the structure and principle of the electro-hydraulic control system, the mathematical model of the electro-hydraulic control system has been established. Being varieties of the working situation of car and the non-linearity of the electro-hydraulic control system, A Fuzzy PID algorithm has been designed. Then the simulation of the belt misalignment has been conducted, and the simulation results show that the electro-hydraulic control system and the fuzzy controller could not only control ratio, which had a higher accuracy of the stable state and a stronger robust of the driving condition, but also eliminated the belt misalignment, improved the dynamic performance of the metal V belt CVT.