The issue studies, in virtue of simulation, temperature control system in air-conditioned coach by fuzzy and PID control methods. The simulation results show that PID control can eliminates steady-state error, but the overtune is big, transitional time is long. And PID control can only suit for air conditioning condition with small variation. For the condition with big variation and time delay, fuzzy control can track the load changes and obtain a better synthetic control quality than PID.