Abstract: A friction model of rough surfaces based on asperities contact can be used to simulate the reciprocating motion of friction pairs with the input parameters of hardness, young's modulus, shear modulus, poisson's ratio, surface roughness, probability density function of asperity height, normal load, and many others. And the friction force-reciprocating distance (F-δ) curves, sliding conditions of asperities can be obtained through thefriction model. The friction behavior of center disc wear plate was studied with the model. The results indicate that the shape of F-δ curves under the reciprocating distances of 2 μm was elliptical. Some of asperities in the contact zone slipped. The F-δ curves change to quasiparallelogram shape under the reciprocating distances of 6 μm and 10 μm.Meantime, all asperities in the contact zone slipped. The surface roughness had little effect on the friction coefficient and friction force. It significantly influenced the slipping properties of asperities.With increasing the surface roughness, the reciprocating distances inducing all asperities slipping increased. And the number of slipping asperities decreased under the same reciprocating distance.