Based on theory of fuzzy control，a combination method of fuzzy control and PID control is used，which is known as fuzzy PID control.A semiconductor laser temperature control system design is completed.It can adaptively adjust PID proportional，integral and differential coefficient to keep the semiconductor cooler’s temperature constant.The simulation results of Simulink show that，after using the fuzzy PID control algorithm the overshoot of the system is reduced by 40%，the adjustment time is shorten and the control effect is better than conventional PID control system.