The present invention provides a membrane-electrode assembly for a fuel cell, having improved durability for repeated start-stop operation. The present invention provides;A membrane-electrode assembly for a fuel cell having: a cathode catalyst layer containing a cathode catalyst comprising platinum or a platinum alloy, conductive carbon material supporting said cathode catalyst, and a proton conductive polymer electrolyte; a solid polymer electrolyte membrane; and an anode catalyst layer containing an anode catalyst, conductive carbon material supporting said anode catalyst, and a proton conductive polymer electrolyte; wherein average thickness (Ya) of said anode catalyst layer is smaller than average thickness (Yc) of said cathode catalyst layer.