In order to prevent the crossover of an organic fuel such as methanol in a
fuel cell and to exhibit excellent electricity generation characteristics
without impairing the utilization efficiency of the fuel, at least either
of (1) a discontinuous catalyst layer being formed on a surface of an
anode catalyst layer and having a higher density (existence probability)
of platinum type catalyst than the anode catalyst layer and (2) an
electrolyte polymer layer is formed at the interface between the anode
catalyst layer and a polymer electrolyte membrane.