Disclosed is an electrolyte membrane-electrode assembly for direct methanol fuel cells, wherein a solid polymer electrolyte membrane is held between a pair of electrodes each composed of a catalyst layer coated over and/or impregnated in a porous supporting body. This electrolyte membrane-electrode assembly for direct methanol fuel cells is characterized in that the solid polymer electrolyte membrane is obtained by irradiating a resin membrane with radiation and graft-polymerizing a radically polymerizable monomer. The electrolyte membrane-electrode assembly for direct methanol fuel cells is further characterized in that the catalyst layer of the anode electrode comprises a catalyst, wherein platinum group metal or platinum-containing alloy particles having a particle size of 5 nm or less are supported by carbon particles, and a solid polymer electrolyte, and the noble metal amount in the catalyst layer of the anode electrode is not more than 5 mg/cm2. By using such a catalyst, there can be obtained a direct methanol fuel cell wherein high output is achieved by using high methanol concentration.