PURPOSE: To enhance the cutting property of high speed steel without deteriorating the toughness thereof, by a method wherein the surface of high speed steel subjected to hardening treatment is irradiated with laser light to dissolve the primary carbide in the surface layer in a matrix to form a solid solution and the irradiated high speed steel is further tempered to finely precipitate the primary carbide.

CONSTITUTION: After high speed steel is once subjected to hardening treatment, the surface thereof is irradiated with laser light of absorption energy density of 2,000J/cm2 or more at a beam moving speed of 2m/min or more to be melted. Hard primary carbides of Mo, W, V or the like in the surface of the high speed steel are dissolved in a matrix to form a solid solution with a uniform crystal structure. The treated high speed steel is subjected to tempering treatment at 500W600°C to precipitate the primary carbides in the solid solution in a fine form and a secondary hardening amount is increased to enhance anti-wear property, that is, cutting property without lowering toughness.