NOVELTY - A fuel cell (100) comprises a fuel electrode (10) that is formed with a tubular form and includes a hydrogen permeable metal; a solid electrolyte membrane (20) that has proton conductivity and is provided on the fuel electrode; and an oxygen electrode (40) that is provided on the solid electrolyte membrane, and that is disposed opposite to the fuel electrode across the solid electrolyte membrane. The fuel cell further comprises a porous base metal plate that is disposed radially inside the tubular fuel electrode to support the fuel electrode. The fuel electrode has a cylindrical shape.    USE - As a fuel cell for generating electric power.    ADVANTAGE - In the fuel cell, the the fuel electrode are formed in the shape of a cylinder having no slits. As a result, the fracture toughness can be enhanced as compared with the case where metal having a slit or slits is used for forming the fuel electrode. In the fuel cell, the fuel electrode, which is tubular in form, has higher strength than a fuel cell of planar design. Also, since the fuel electrode is formed of metal, the fuel cell has high fracture toughness. Thus, in the fuel cell, the fuel electrode may be formed with a small thickness (i.e. 5-100 mu m) while assuring adequate strength. With the thickness of the fuel electrode thus reduced, the energy required for starting the fuel cell is reduced. The size of the fuel cell can be reduced. Since the fuel electrode takes the form of a dense metal layer, the thickness of the electrolyte membrane formed on the fuel electrode may be reduced. Consequently, the power generation efficiency of the fuel cell is enhanced.    DETAILED DESCRIPTION - A fuel cell (100) comprises a fuel electrode (10) that is formed with a tubular form and includes a hydrogen permeable metal; a solid electrolyte membrane (20) that has proton conductivity and is provided on the fuel electrode; and an oxygen electrode (40) that is provided on the solid electrolyte membrane, and that is disposed opposite to the fuel electrode across the solid electrolyte membrane. The fuel cell further comprises a porous base metal plate that is disposed radially inside the tubular fuel electrode to support the fuel electrode. The fuel electrode has a cylindrical shape. The fuel electrode is formed with the form of an elliptical tube, a rectangular tube, or a flat tube. A first catalyst that promotes dissociation of hydrogen molecules into protons is provided between the fuel electrode and the solid electrolyte membrane. A second catalyst that promotes dissociation of hydrogen molecules into protons is provided radially inside the fuel electrode such that the second catalyst is opposed to the first catalyst.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic perspective view of fuel cell, and a cross-sectional view of fuel cell.    Fuel electrode (10)    Fuel gas channel (11)    Solid electrolyte membrane (20)    Oxygen electrode (40)    Fuel cell (110)