A cladding method for a valve seat in a cylinder head blank includes a combustion chamber, an intake port or an exhaust port communicating with the combustion chamber, and an annular countersunk groove formed in an opening end of the port on the combustion chamber side, the method being for forming a cladding layer by irradiating metal powder supplied in the countersunk groove with a laser beam. A gas flow regulating wall is provided, which projects from the countersunk groove to an inner side of the countersunk groove and to the combustion chamber side, gas is sprayed during irradiating with the laser beam, and the gas is flown by the gas flow regulating wall from the inner side to an outer side of the countersunk groove.