NOVELTY - A porous support-hydrogen permselective-membrane substrate has hydrogen permselective membrane formed in the surface of a porous support containing porous base material. 1 or more coating membrane is formed on the surface of porous base material. The average pore diameter of open pore contained in the coating membrane is smaller than the average pore diameter of open pore contained in porous base material.    USE - Porous support-hydrogen permselective-membrane substrate is used for anode of porous support type fuel cell (claimed) for vehicle-mounted motive power source, fixed type small electric power generation device and cogeneration system.    ADVANTAGE - The hydrogen permselective membrane is thin, smooth, economical, free from pinholes and has uniform thickness. The anode comprising porous support-hydrogen permselective-membrane substrate has improved gas permeability. The fuel cell has high electric power generation performance.    DETAILED DESCRIPTION - A porous support-hydrogen permselective-membrane substrate has hydrogen permselective membrane formed in the surface of a porous support containing porous base material. 1 or more coating membrane is formed on the surface of porous base material. The average pore diameter of open pore contained in the coating membrane is smaller than the average pore diameter of open pore contained in porous base material. The porous support consists of intermetallic compound containing nickel, iron and/or cobalt, alloy containing nickel, iron and/or cobalt, alumina, zirconia, cordierite, spinel, mullite, silicon nitride, silicon carbide, sialon, zirconium, magnesia and/or aluminum titanate, metal of group 4-6, carbide, boride, silicide, nitride and/or oxide of group 4-6 metals or their complex compound. The coating membrane has powder layer containing multilayer powder. The multilayer powder contains easily sinterable metallic element as main component and difficulty sinterable metallic element as subsidiary component. The easily sinterable metallic element is chosen from iron, cobalt, nickel, silver, molybdenum, gold and/or copper. The difficulty sinterable metallic element is chosen from 2A group element, aluminum, barium, indium, silicon, germanium, manganese, tungsten, rhenium, titanium, zirconium, chromium, scandium, yttrium, ytterbium and/or zinc. The hydrogen permselective-membrane is palladium film or palladium alloy film or laminated film of palladium film or palladium alloy film, joined on surface(s) of metal film. The metal film contains a metal having body centered cubic structure. The metal is vanadium, tantalum or niobium. The palladium alloy film consists of palladium-silver alloy, palladium-gold alloy, palladium-copper alloy, palladium-nickel alloy, palladium-manganese alloy, palladium-chromium-nickel alloy, palladium-platinum alloy, palladium-rhodium alloy, palladium-silver-ruthenium alloy or palladium-silver-nickel alloy.    DESCRIPTION OF DRAWING(S) - The drawing shows the schematic block diagram of porous support type fuel cell. (Drawing includes non-English language text)