NOVELTY - The conductive porous material comprises a framework of plastic porous material with continuous pore structure, provided with a nickel conductive layer exhibiting uninterrupted conductivity. The conductive layer is formed by depositing nickel from solution containing nickel ions of average particle diameter 10-300 nm, in presence of a reducing agent.    USE - For use in metallic porous material used as battery plate (both claimed), in alkaline secondary batteries. The metallic porous material can also be used as carrier for various catalysts, as component for various space heaters, for gasifying or atomizing heating oil and burner port plate for gas, for silencer of engines and pneumatic apparatus, for oil-mist separator, for catching soot in exhaust gas of diesel engines, as component for shielding electromagnetic waves, for filters, for pistons of diesel engines and as wear-resistant components in hydraulic apparatus.    ADVANTAGE - The nickel-ion reducing substance has a sufficient reducing potential for reducing nickel ions, and extremely large ionization tendency and hence cannot be reduced by metals in an aqueous solution. The reducing agent does not contaminate nickel layer as an impurity metal during electroplating, and can be re-used by restoring original oxidation number easily even if it is oxidized, by acting as reducing agent. The impurities in conductive layer is reduced to minimum and metallic layer that is easy to handle, is provided at high growth rate with high production efficiency, and is capable of providing an excellent porous material with low electrical resistance. The battery plate has high charging and discharging efficiency and bonding strength of the conductive particles and framework is improved. Nickel ions are deposited directly from aqueous solution without using noble metal such as palladium. The adhesion of nickel to porous material is enhanced by causing the porous material to adsorb titanium chloride. Catalyst is not required for formation of nickel layer. The conductive layer comprising nickel particle forms thin passive coating which is resistance to water and oxygen. The conductive porous material has excellent conductivity, which does not decrease by deformation such as drawing or bending. Production of metallic porous material having superior productivity, production efficiency and low electrical resistance, is enabled.