When electricpneumatic valve positioner regulates the valve opening, large overshoot will be generated in the PID process. Natural deflating or adding antireaction will be adopted to adjust the valve position, but the system robustness and control efficiency will be greatly affected. A genetic optimization PID tuning algorithm is proposed in this paper, based on the relay feedback method to estimate the system PID parameters roughly, then the improved genetic algorithm is used to optimize the PID parameters. The proposed methods enable the system to realize control without overshoot, improve the control accuracy, and shorten the adjustment time. In the process of controlling the pneumatic regulating valve with PID parameters obtained by this system, the overshoot can be controlled under 06%, and the adjusting time can be shortened by 66% compared with the traditional PID algorithm. Simulation and experiment results show that the proposed algorithm can realize stable, accurate and fast control mode, and this idea is proposed to optimize the control strategy of electricpneumatic valve positioner.