NOVELTY - The fuel cell stack (10) has unit cells (12) that are provided with electrolyte electrode assembly and separators. A load receiver is provided to receive a load in a direction perpendicular to stacking direction of unit cells. The load receiver is made of resin. A projection is protruded from outer end of separator. A recess is depressed from outer end of separator. The load receiver is depressed to form an inner curve. The inner curve of load receiver is designed to provide flexibility in a direction perpendicular to the stacking direction.    USE - Fuel cell stack e.g. solid polymer electrolyte fuel cell used as driving source of automobile.    ADVANTAGE - The fuel cell stack in which the impact load is received by load receivers is manufactured efficiently. The load receiver to which the impact load is applied is deformed easily, and placed in alignment with the other load receivers, when external force such as an impact load is applied to any of load receivers. Since the external force is distributed to the load receivers, the concentration of the external force on the single load receiver is avoided such that damage of the load receiver is prevented. The detachment of the unit cells from the fuel cell stack is prevented. Since the damaged position is spaced away from the separator, the exposure of the separator resulting from the damage of the load receiver is avoided. The formation of electrically conductive channel through the separator is avoided such that desired insulating performance is maintained efficiently. The flexibility of load receiver is improved. Both ends of the positioning pin are fitted to the other holes without any clearance. Since the plate shaped section is provided with recesses, the weight reduction is achieved. The bending strength of the plate shaped section is improved. The thickness of the tightening element is reduced. The concentration of the force on the projecting load receiver or the recessed load receiver is reduced. The simple and compact structure of the fuel cell stack is ensured. The positional displacement of the stacked unit cells is suppressed. The damage of the positioning pins is prevented.    DESCRIPTION OF DRAWING(S) - The drawing shows a perspective view of the fuel cell stack.    Fuel cell stack (10)    Unit cells (12)    Stack portion (14)    Tightening elements (24,26)    Oxygen-containing gas supply passage (40)