The object of the invention is to provide a separator for fuel cells which is of improved strength and corrosion resistance and facilitates the assembling of unit cells. The separator comprises an electrically conductive resin layer formed by electrodeposition in such a way as to cover a metal substrate and a gasket component. The resin layer contains an electrically conductive material. The separator of the invention has thus an enhanced corrosion resistance, makes some considerable improvements in the assembling work efficiency of unit cells, and makes sure higher strength because of the use of the metal substrate.