Separator and fuel cell using that separator

A separator of a fuel cell, which is inserted between single cells, each single cell having an electrolyte sandwiched between electrodes, in order to stack the single cells together, includes gas diffusion portions which are arranged so as to cover a surface of the electrodes and in which are formed multiple air holes for gas diffusion, and spacer portions which form parallel divided gas passages on the back side of portions of the gas diffusion portions which cover the surface of the electrodes. The gas diffusion portions and the spacer portions are integrally formed by bending a wire mesh member to have a rectangular corrugated plate shaped cross-section. As a result, the air holes are formed evenly between the electrodes and the separator and high contact pressure is ensured by the contact of the fine wire mesh, thereby making it possible to both have the gas diffuse evenly and reduce the power collection resistance.