TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Compounds: The chloride of platinum is at least one type of compound chosen from chloroplatinic acid hexahydrate, platinum chloride, platinum chloride potassium, potassium chloroplatinate and platinic acid potassium tetra chloride. The salts or complexes of ruthenium are ruthenium chloride hydrate, ruthenium chloride anhydride, ruthenium acetate, ruthenium nitrate, ruthenium triphenyl phosphine complex, ruthenium ammine complex, ruthenium ethylenediamine complex and/or ruthenium acetyl acetonate complex, preferably tris(acetyl acetonate)ruthenium (III). Preferred Method: Adjustment of pH value of the alcohol solution is performed using an aqueous solution of alkali, preferably aqueous solution of sodium hydroxide.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Compounds: The chloride of platinum is at least one type of compound chosen from chloroplatinic acid hexahydrate, platinum chloride, platinum chloride potassium, potassium chloroplatinate and platinic acid potassium tetra chloride. The salts or complexes of ruthenium are ruthenium chloride hydrate, ruthenium chloride anhydride, ruthenium acetate, ruthenium nitrate, ruthenium triphenyl phosphine complex, ruthenium ammine complex, ruthenium ethylenediamine complex and/or ruthenium acetyl acetonate complex, preferably tris(acetyl acetonate)ruthenium (III). Preferred Method: Adjustment of pH value of the alcohol solution is performed using an aqueous solution of alkali, preferably aqueous solution of sodium hydroxide. EXAMPLE - Ethylene glycol (160 ml) was made to dissolve ruthenium (III) chloride (1.69 mmol), in ethylene glycol solution (160 ml) containing dispersed carbon powder (0.5 g). Subsequently, chloro platinic acid hexahydrate (1.69 mmol) was dissolved in the solution. 2N sodium hydroxide aqueous solution was added, and pH was adjusted to 9-10. The reaction mixture was refluxed, by stirring at 200degreesC by nitrogen atmosphere, and carbon powder was made to support platinum-ruthenium alloy catalyst microparticles. The resulting product was filtered and dried, and platinum-ruthenium alloy catalyst was obtained. The catalyst had excellent methanol oxidation activity.