The mixed traffic flow, which is composed of different types or performances motor vehicles, is the common phenomenon in road traffic. On the periodic boundary condition, motor vehicles mixed traffic flow of one-way and single lane is the target of research. Based on the improved FI model, the rules of safe driving are considered. And the one-dimensional cellular automation FI traffic flow model of different velocity mixed motor vehicles is presented. The driving state of the vehicles in front is considered in this model. The new model presented in this paper is simulated. According to the results of simulation, by taking the new model presented this paper compared with the improved FI model, the value of observed velocity is not negative. And there is no the phenomenon of stop when driving and the area of stagnation. The model of this paper is accorded with actual traffic flow phenomena.