Based on statistics model,Greenwood and Tripp (GT model) have proposed that the normal contact between two rough surfaces(tworoughsurface model) could be equivalent as a single rough surface in contact with a rigid flat (singleroughsurface model).However,this equivalence treatment lacks the analysis of contact stress field as well as the consideration of material hardening.In order to further elaborate the GT model by means of Gaussian rough surface,by means of autocorrelation length and filter approach,the rough surface in the tworoughsurface model and the equivalent rough surface in singleroughsurface model were all obtained perfectly.By virtue of finite element method (FEM),the tworoughsurface model and the equivalent singleroughsurface model were developed and analyzed.The results show that the predicted contact stiffness and contact area by the two models have great agreements with each other,but the relationship between contact force and contact area is different.The distribution of equivalent stress and contact pressure predicted by the two models are roughly the same,but their amplitudes in tworoughsurface model are slightly lower than those in singleroughsurface model due to the effect of shouldertoshoulder contact,which weakens the contact status and material hardening