Abstract: An arrangement for tightening a stack of fuel cell elements, each cell element including a cathode, an anode and a tile sandwiched by the cathode and the anode and the cell elements being piled up one after another with separators being interposed therebetween, comprising an upper and a lower holders for holding the fuel cell stack, an upper and a lower pressure-adjusting members for sandwiching the upper and lower holders, each pressure-adjusting member including a hollow body constructed by welding two thin, metallic plates and gas enclosed in the hollow body, an upper and a lower adiabatic materials for sandwiching the pressure-adjusting members, and a pressing device for pressing the upper and lower adiabatic materials, the adiabatic materials, the pressure-adjusting members, the holders and the fuel cell stack, wherein the pressing force of the pressing device is given to the holders and the fuel cell stack through the pressure-adjusting members in the form of an uniform pressure.