In order to improve the traffic capacity of the intersection under the mixed traffic flow environment of autonomous vehicles and regular vehicles, the maximum traffic capacity of the intersection is set as the objective function. Then dedicated lanes for autonomous driving, dedicated lanes for regular driving and mixed driving lanes are set up in the intersection. Moreover, this paper establishes an optimization model based on lane layout and signal timing, and solves it. The research results show that the model in this paper can effectively improve the traffic capacity of the intersection by setting corresponding lanes and performing signal timing. The sensitivity analysis of the proportion of autonomous vehicles in the traffic flow, the headway of the dedicated lane for autonomous driving and the headway of the dedicated lane for human driving show that the proposed model can be applied to a variety of different traffic conditions.