A membrane electrode assembly for a polymer electrolyte fuel cell has superior power generation characteristics under low humidity conditions and superior starting characteristics under low temperature conditions. In the membrane electrode assembly for a polymer electrolyte fuel cell in which a polymer electrolyte membrane is disposed between a pair of electrodes containing a catalyst, the polymer electrolyte membrane has a polymer segment A having an ion conductive component and a polymer segment B not having an ion conductive component. Furthermore, in the case in which the polymer electrolyte membrane is immersed in water at 90.degree. C. for 30 minutes, absorbed water which exhibits a thawing temperature of from -30 to 0.degree. C. is in a range from 0.01 to 3.0 g per 1 g of the polymer.