In a planar-array cell structure, an area required by interconnectors is reduced and a fuel cell is made further compact. A connection part which connects adjacent cells in series is provided within a sealing member provided in a peripheral edge part of an electrolyte membrane where multiple cells are formed in a planar arrangement. For each cell, an anode terminal of a current collector is disposed counter to a cathode terminal of the current collector via the electrolyte membrane. The connection part penetrates the electrolyte membrane and connects the anode terminal of one of the adjacent cells to the cathode terminal of the other of the adjacent cells.