The present invention provides a method for producing a catalyst for a fuel cell comprising: a step for forming an inverted micelle consisting of an aqueous solution containing the iridium compound clathrated by a surfactant, by mixing an organic solvent containing said surfactant, and the aqueous solution containing said iridium compound; a step for forming a fine iridium particle aggregate by insolubilization treatment of said iridium compound; a step for impregnating said fine iridium particle aggregate with an aqueous solution containing a platinum compound; a step for obtaining a solution containing the inverted micelle clathrating the fine iridium particle aggregate containing platinum by reducing said platinum compound and depositing platinum metal in said fine iridium particle aggregate; a step for supporting said fine iridium particle aggregate containing platinum on a conductive carrier by dispersing said conductive carrier in said solution; and a step for firing the conductive carrier whereon said fine iridium particle aggregate containing platinum is supported.