To improve the simulation accuracy for adaptive cruise control (ACC) system, the hardware in the loop simulation (HILS) platform with real actuators of ACC is developed in this paper. The HILS platform consists of simulation model parts running in the simulation instrument and hardware parts including the electronic throttle and active braking system. In the simulation model, radar simulator, controller of ACC and vehicle mode are developedin order to generate the traffic information, the control command of ACC system and calculate the motion of vehicle. By using the desired control values transmitted from the ACC’s controller, the hardware parts could realize throttle openness and braking pressure tracking control. The simulation experiments of ACC are carried out based on this HILS platform, and the simulation results confirm that the HILS platform could work in a proper way and could be used as a simulation platform to develop the controller of ACC.