In view of the widespread rough surface contact of robot reducer,the relevant research was carried out.On the basis of GW contact model,considering the effects of interaction during rough peak contact,a new model was obtained by modifying it.The modified model was adopted to calculate the contact load and contact stiffness of the rough surface,and then the results were compared with those of the original GW contact model.In the further study,the effects of surface roughness and contact surface materials on contact load and contact stiffness were discussed.The result shows that the contact parameters of the rough surface are not only affected by the interaction of the rough peaks,but also have a close relationship with the roughness and the contact surface material.