In order to provide a constituting part for a fuel battery in which a number of steps of assembling the constituting parts for the fuel battery can be reduced, and in which the replacing property and the maintenance property of fuel battery cell parts can be improved and the cost for parts can be reduced, the structure is made such that a separator made of a carbon plate or substantially similar material, a gas diffusion layer made of a carbon fiber or substantially similar material, and a gasket made of a liquid rubber cured material or substantially similar material are integrally formed, and further, gaskets are respectively provided on both surfaces of a pair of gas diffusion layers holding an independent electrolyte membrane from both sides thereof between the pair.