An electrochemical galvanic sensor for hydrogen determination in air is reported. It is based on a solid-state electrolyte with high proton conductivity at an ambient temperature, regeneratable electrode materials and is fabricated with planar technology as a pellet with the dimensions 12 x 5 mm and mass similar to 5 g. During the sensor function the gas molecules are oxidized on the sensitive electrode connected with the counter electrode which contains as a catalyst macrocyclic or macrobicyclic polyaza cobalt(III) complexes. The sensor shows good sensitivity, stability and repeatability of the output signal, sufficient response time -T-90 is less then 15 s, low humidity dependency and long operating life of up to several years.