A process for preparing a metallic porous body, comprising: forming a layer comprising Cu, a Cu alloy, or a precursor thereof onto a skeleton composed of a porous resin body having a three-dimensional network, heat-treating the resin body with the layer formed thereon to remove a heat-decomposable organic component, thereby forming a porous metallic skeleton of Cu or a Cu alloy; and plating the surface of the Cu or Cu alloy skeleton with Ni or an Ni alloy. The heat treating may be carried out by direct induction heating. The metallic porous body is useful as electrodes for batteries, various filters, carriers for catalysts, etc. When the porous body is cut and used as the electrode substrate, the coating of an area, where Cu or its alloy has been exposed by cutting or the like, with a third metal having a lower ionization tendency than Cu or its alloy can provide an electrode substrate having better corrosion resistance and battery service life.