In this paper the structure and wear resistance of laser strengthened W18Cr4V high speed steel are studied, and the cutting property and failure form of the tools are discussed. The test results indicate that the properties of the laser strengthened layer have been improved greatly compered with those of the steel and tools heat-treated commonly.The hardness can reach 1000Hv0.1. The toughness of laser strengthened layer is also improved remarkably, and the wear resistance is increased by 2～8 times. The service life of laser strengthened cutting tools of high speed steel can be prolonged by 2～5.7 times than the non-laser-treated ones.