The invention provides a solid polymer electrolyte having high performances in which the reaction area of electrode is increased by uniformly dispersing and bonding a solid polymer electrolyte and a catalyst and the ability of gas feeding to the reaction site is improved by adding a fluoropolymer so that the catalyst is not excessively coated. A method for making the fuel cell is also provided. The electrode provided on at least one side of a solid polymer electrolyte membrane is formed by coating on one side of a gas-diffusible layer a mixed dispersion of a noble metal catalyst, a carbon fine powder and a colloidal dispersion of a solid polymer electrolyte, the colloidal dispersion being prepared using an organic solvent having a polar group other than hydroxyl group in the molecule and having a carbon chain of 1-8 carbon atoms which bonds to the polar group or having a dielectric constant of 3-10.