In order to solve the problem of blind area in the corners and improve driving safety when driving at night. One AFS model was established based on steering wheel angle,and another AFS model was established based on the preview angle. the control algorithms of headlights’ horizontal angle adjustment were established in the matlab / simulink. Simulation results of 40km/h, 60km/h,80km/h and 100km/h shows that the headlight horizontal adjustment angle is not sensitive to the variation of speed; The curve of horizontal adjustment angle of AFS based on the angle preview is smoother, and the adjustment angle does not appear suddenly increases and decreases.