According to the requirements of European child restraint system regulations ( ECE \ R129) ,a finite element model considering a trolley seat,a child seat,a child dummy and a safety belt is established by using the related software.Then,the collision process is simulated and analyzed with Ls-dyna according to the conditions of the front and the rear crash experiments,finding that the movement patterns as well as the dummy's head and thorax accelerations in the collision process are consistent with the experimental ones,which means that the simulation model is effective.Finally,a finite element model to describe the side impact is built by introducing a side plate instead of the vehicle side doors,which is used to analyze the side impact situations of car child safety seat.The results show that the peak accelerations of dummy's head and chest in side impact situations are both greater than those in the front and rear crash situations,which means that it is necessary to develop and implement side impact regulations for automobile child restraint systems.