NOVELTY - A sulfurous-acid electrolysis cell (1) comprises an anode gas diffusion electrode layer (3) arranged on one surface side of a cation exchange membrane (2), and a cathode gas diffusion electrode layer (4) arranged on another side of cation exchange membrane. The sulfurous-acid electrolysis cell performs electrolyzing sulfurous acid supplied to anode gas diffusion electrode layer, and thus sulfuric acid is generated from anode gas diffusion electrode layer side, and hydrogen is generated from cathode gas diffusion electrode layer side.    USE - Sulfurous-acid electrolysis cell is used for generating hydrogen.    ADVANTAGE - The sulfurous-acid electrolysis cell has high electrolysis capability and hydrogen-producing capability, and effectively prevents the voltage loss of electrolysis. The storage of dilute sulfuric acid in wall improves conductivity of hydrogen ion in dilute sulfuric acid flow path.    DETAILED DESCRIPTION - A sulfurous-acid electrolysis cell comprises an anode gas diffusion electrode layer arranged on one surface side of a cation exchange membrane, and a cathode gas diffusion electrode layer arranged on another side of cation exchange membrane. The sulfurous-acid electrolysis cell performs electrolyzing sulfurous acid supplied to anode gas diffusion electrode layer, and thus sulfuric acid is generated from anode gas diffusion electrode layer side, and hydrogen is generated from cathode gas diffusion electrode layer side. The sulfuric acid generated from the anode gas diffusion electrode layer side between anode gas diffusion electrode layer and cation exchange membrane is flushed out in dilute sulfuric acid flow path (5). A through-hole (12) is penetrated through a gas seal portion and cathode gas diffusion electrode layer of cation exchange membrane in lamination direction, and the sulfuric acid flows via the through-hole. A dilute-sulfuric-acid is supplied by flowing from cathode side and the dilute-sulfuric-acid flow path is formed in such manner that boundary of anode gas diffusion electrode layer and gas sealing portion is avoided.    DESCRIPTION OF DRAWING(S) - The drawing shows a sectional view of principal portion of sulfurous-acid electrolysis cell.    Sulfurous-acid electrolysis cell (1)    Cation exchange membrane (2)    Anode gas-diffusion-electrode layer (3)    Cathode gas-diffusion-electrode layer (4)    Dilute sulfuric acid flow path (5)    Through-hole (12)    Wall (16)