Laser remelting of surface of cobalt-based hardfacing alloy can eliminate impurities and cracks and improve the wear resistance. In this present study, Stellite ${sharp}6;and;{sharp}21$ harfacing alloys were remelted by a 3kW CO2 laser. Hardness distribution and microstructures in the laser remelted zone was investigated. Our results showed that in proper laser parameters laser remelted surface of hardfacing alloy had more refined microstructure and more increased micro-hardness than the base material.