The present invention relates to a fuel cell including a plurality of unit membrane electrode assemblies having an electrolyte membrane sandwiched by fuel electrodes and air electrodes. In recent years, attempts have been made to use fuel cells as power sources of portable electronic devices, and if the fuel cell can be made compact, it becomes a remarkably advantageous power supply system for portable electronic devices. Generally, in the fuel cell, the plural unit membrane electrode assemblies are electrically connected in series, but the serial connection of the unit membrane electrode assemblies different in output has a problem such as the deterioration due to polarity reversal occurring in the unit membrane electrode assembly with a low output. The present invention solves the above problem by the structure in which the fuel cell includes: the membrane electrode assembly group in which the plural unit membrane electrode assemblies are arranged two-dimensionally so as to be a predetermined interval apart from each other in a circumferential direction around a given center point, with the same electrodes being set on the same side; and a fuel supply mechanism disposed on the fuel electrode side of the membrane electrode assembly group and supplying a fuel to the fuel electrodes.