There is provided a polymer electrolyte fuel cell which comprises a pair of electrodes, a polymer electrolyte membrane interposed between the pair of the electrodes, a first conductive separator having a channel for supplying an oxidant gas to one of the electrodes therethrough, and a second conductive separator having a channel for supplying a fuel gas to the other of said electrodes therethrough, wherein at least one of the electrodes comprises a porous catalyst layer formed on the surface of the polymer electrolyte membrane, or formed on the surface of a porous conductive base material, the porous catalyst layer facing the polymer electrolyte membrane.