Mixed-traffic that contains motorized and nonmotorized vehicles become more common in urban areas. Compare with motorized traffic, nonmotorized traffic flow theory isn't mature enough. In this study, a motorcycle traffic flow model is proposed. It contains longitudinal and lateral movement models. The motorcycle traffic flow is influenced by driver characteristics, vehicle interactions, and the external environment all of which the proposed model will take into account. Finally, a motorcycle traffic flow simulation is presented. The simulation result indicates that the proposed model is reasonable, and it can reflect some motorcycle traffic flow phenomena. The behaviors of bicycles and pedestrians are similar to motorcycles; the result of this study could be the basis of bicycle or pedestrian flow model.