The normal press is more sensitive to roughness at the rough convex peak points is twice to three times as the Hertzian stress when Ra=0.4 μm if oil film thickness is less than 0.5μm at contact areas. The direct contact at rough peak will lead to a larger stress. The surface roughness with big value results in severe stress concentration at both surface and subsurface. The shear stress is obvious concentrating at both sides of contact areas