The work aims to know if laser shock processing can be used to prolong the service life of M2 high-speed steel cutting tools by studying mechanism of effects of laser shock processing treatment on surface properties of W6Mo5Cr4V2(M2) high-speed steel. With aluminum foil as a surface absorbing layer and running water as a constraining layer, laser shock processing was performed to M2 high-speed steel cutters using high-power Nd glass laser shock system. Then the surfaces of specimens were grinded with sandpaper and polished with abrasive paste. The metallographic specimens were eroded with nitric-acid-alcohol solution. Microstructures of strengthened layer of shocked specimens were observed and analyzed with metallographic microscope and scanning electron microscope. Surface microhardness of specimens before and after laser shock processing was measured with hardness tester. Surface residual stress of shocked specimens was measured with X-ray stress analyzer. Provided with laser wavelength of 1064 nm, laser energy of 9 J, spot diameter of 3 mm, pulse width of less than 12 ns and laser power density of 12.7 GW/cm2, austenite grains in the strengthened layer of M2 steel were refined significantly, and mixed microstructure of dislocated martensite and twinned martensite was produced. The surface hardness after LSP increased slightly by 6.67%, compared with that before LSP. A nearly 1.0 mm deep residual compressive stress layer was obtained on the surfaces of specimens, and the maximum residual compressive stress of about ?155 MPa was present in the outermost layer. To a certain degree, laser shock processing treatment improves surface properties of M2 high-speed steel, therefore contributing to the improvement of cutting performance and service life of M2 high-speed steel cutting tools.