Abstract: Not all gas diffusion structures known to date can guarantee water balance compensation in the fuel cell, protection against drying and prevention of water deposits while simultaneously ensuring even distribution of reaction gases. In the gas diffusion structure, according to the invention, a gradient is produced in terms of gas permeability perpendicular to the membrane by way of a stratified system. This guarantees, at an appropriate operating temperature and appropriate stoichiometry of the reactants, constant and optimal humidification in all points of the membrane by the formed product water. Additional humidification systems can thus be discarded.