Abstract: The contact condition of rail was simulated with twin-disk in laboratory. Effects of creepages and contact stresses on wear behaviours in pearlitic rail steel have been studied, based on the appearance observations and surveying below surface by SEM, the wear forms and their mutual effects in wear process have been approached. It is concluded that wear rates increase with both creepage level and contact pressure. The friction coefficients increase with creepages and when creepages rise to 4%, the limiting friction coefficient is reached. Mass loss is linear with sliding friction works and in proportion to sliding distances. Microstructures below surface show intense plastic deformation in dry wear and lamellarly distribute aling the direction of paralleled with surface. Adhesive wear and surface-fatigue wear are the two major wear forms in rail steel.