A sensor element for limiting current sensors for determining the .lambda. value of gas mixtures is proposed which has two interconnected inner pump electrodes (8 and 8') disposed opposite each other in a diffusion channel (7). The resulting increase of the effective surface at the beginning of the inner electrodes markedly reduces the disadvantageous electrode polarization which occurs in sensor elements having only one inner pump electrode. At the same time, a better utilization of the noble metal required to form the pump electrodes is achieved.