Abstract: A tuyere for a melting furnace, which comprises inner and outer walls forming a water cooling space therebetween; a cylindrical intermediate wall dividing the water cooling space into an inner water cooling chamber and an outer water cooling chamber, whereby the cooling water is first introduced into the outer water cooling chamber from the outside of the furnace, circulated into the inner water cooling chamber from the inner end portion at the furnace side of the outer water cooling chamber and thereafter discharged from the outer end portion of the inner water cooling chamber; and a guide wall disposed in the outer water cooling chamber so as to form a helical passage for the cooling water, said helical passage being so devised that a portion of the passage located so as to be subjected to a relatively high heat load has a cross-sectional area smaller than that of other portions of the same.