NOVELTY - A membrane-electrode assembly (20) has electrode catalyst formed using base metal complex. The membrane-electrode assembly has exchange current of 5x 10-4 Acm-2 or more as determined from Tafel plot regarding current density and voltage, and Tafel slope is 450 mV/decade or less.    USE - Membrane-electrode assembly for fuel cell (claimed) e.g. polymer electrolyte fuel cell and direct methanol fuel cell used as power supply for mobile machines such as mobile telephone and portable personal computer, domestic power supply, and power supply of motor vehicles.    ADVANTAGE - The membrane-electrode assembly having excellent stability, is manufactured economically. Fuel cell comprising membrane-electrode assembly has excellent electric power generation efficiency.    DETAILED DESCRIPTION - A membrane-electrode assembly has electrode catalyst formed using base metal complex. The membrane-electrode assembly has exchange current of 5x 10-4 Acm-2 or more as determined from Tafel plot regarding current density and voltage, and Tafel slope is 450 mV/decade or less. The base metal complex contains compound having two or more phenol rings and two or more aromatic heterocyclic rings as ligand. Base metal complex contains vanadium, chromium, manganese, iron, cobalt, nickel, copper, zirconium, niobium, molybdenum, tantalum and/or tungsten as base metal atom. The number of base metal atom contained in one molecule of base metal complex is 1-10. Membrane electrode assembly comprises catalyst layers (14a,14b) containing electrode catalyst provided on both sides of electrolyte membrane (12). At least one catalyst layer contains non-noble metal type electrode catalyst which uses non-noble metal complex. The electrolyte membrane is hydrocarbon type electrolyte membrane which contains aromatic-hydrocarbon type polymer electrolyte.    DESCRIPTION OF DRAWING(S) - The drawing shows the longitudinal cross-sectional view of the fuel cell.    Fuel cell (10)    Polymer electrolyte membrane (12)    Catalyst layers (14a,14b)    Gas diffusion layers (16a,16b)    Separators (18a,18b)    Membrane-electrode assembly (20)