An object of the present invention is to provide a method for producing fine catalyst particles, a method for producing carbon-supported fine catalyst particles, a method for producing a catalyst mix, and a method for producing an electrode, all of which are configured to inhibit, when used in fuel cells, etc., performance deterioration during operation at especially high temperature. Disclosed is a method for producing fine catalyst particles each comprising a core particle and an outermost layer, the core particle containing palladium and the outermost layer containing platinum and covering the core particle, the method comprising the steps of: preparing palladium-containing particles; preparing an acid solution configured to dissolve palladium more preferentially than platinum; covering each palladium-containing particle with an outermost layer containing platinum; and bringing the palladium-containing particles each covered with the outermost layer into contact with the acid solution.