NOVELTY - A solid-polymer water electrolyzer (20) provided in pressure vessel (21), has electrode contact film, anode and cathode power supplies between double plate electrodes. The electrolyzer water route is formed horizontally with parallel rows, either at plate front/back. The hydrogen gas generated in electrolyzer is distributed through removal unit (22) provided at vessel top.    USE - For supplying hydrogen gas at hydrogen station for fuel cells.    ADVANTAGE - Since the electrolyzer water route is formed horizontally with parallel rows, the entire electrolytic cell is cooled uniformly and the flow amount of electrolyzed water is increased. Hence the electrolyte film is prevented from damage.    DETAILED DESCRIPTION - The anode power supply, electrode contact film, cathode power supply that are provided between the double plate electrodes, are arranged perpendicularly with respect to horizontal water routes which is connected to hydrogen header and through which electrolyzed water of each hydrogen cell, and oxygen passes. The hydrogen removal unit provided at vessel top, has hydrogen gas separation layer (32) which is impregnated palladium into vessel top. A non-return-valve type pressure valve (34) is opened to pass hydrogen gas to hydrogen line (23), when the pressure of hydrogen gas reaches preset pressure. The double plate electrodes periphery are attached with O-rings. The electrolyzer is pushed against bottom wall of container pressed with lid to form pressure vessel, by electrolytic cell pressing. A hydrogen vapor liquid separation portion including electrolyzed water layer and hydrogen gas layer, is formed between vessel lid and electrolyzer upper surface.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic view of hydrogen supply apparatus. (Drawing includes non-English language text).    solid-polymer water electrolyzer (20)    pressure vessel (21)    hydrogen gas removal unit (22)    hydrogen line (23)    hydrogen gas separation layer (32)    non-return-valve type pressure valve (34)