Abstract: A fuel cell comprises unit cells stacked through separators therebetween; each unit cell comprising a fuel electrode plate, an oxidizing agent electrode plate and a matrix between electrode plate and the oxidizing agent plate, U-shaped gas flow passages for the fuel electrode and for the oxidizing agent electrode are provided in a counter-current relation to each other with gas inlets and gas outlets for the fuel electrode and the gas inlets and the gas outlets for the oxidizing agent electrodes being provided at the opposite sides of the fuel cell, respectively, and communicated respectively with manifolds at the same opposite sides of the fuel cell. The fuel cell is simple in structure, highly reliable in fabrication, operation and maintenance, and high in gas utilization efficiency.