For practical operation conditions of engine cylinder, piston speed and lateral pressure to cylinder wall are determined as experimental factors. According to load and speed on 1mm~8mm below top dead center of cylinder in expansion stroke, the ranges of experimental parameters are chosen. Based on the quadratic regression rotation combination method, wear resistance experiment of hardening material is designed. The wear mathematic models of Ni-P electroless plating is established, and three-dimensional curved surfaces for load-speed-wearing value are drawn. The results show that the Ni-P electroless plating can increase relative wear resistance of cylinder by 5 times. By analysis of wear mechanisms of hardening material and wear resistance, the material is perfect for hardening engine cylinder wall.