Disclosed is a method of manufacturing a membrane-electrode assembly for fuel cells. The method includes (a) admixing a metal catalyst, an ionomer and a first dispersion solvent to prepare a first admixture, (b) heat treating the first admixture prepared in (a) to form an ionomer-fixed metal catalyst, and (c) immersing the ionomer-fixed metal catalyst formed in (b) in a solvent, wherein the solvent in (c) may include one or more selected from the group consisting of ethanol, propanol, and isopropyl alcohol. The membrane-electrode assembly for fuel cells manufactured by the method may have substantially improved durability.