Abstract: An electrochemical gas sensor for detecting gaseous components in the environment has a diffusion membrane, a measuring electrode, a counterelectrode, and, if desired, a reference electrode, pressed together in a disk stack, which are accommodated in a pot-shaped cover, which in turn is beaded around the sealing edge (6) of a housing pot (1). A compression spring (21) in the housing pot (1) presses a wick disk (20) against the measuring electrode (12), so that a constant and pressurized, intimate and sealed positioning of the disk stack is guaranteed. It is achieved as a result that no additional contact leads from the electrodes to the outer space of the sensor to the measuring and evaluating unit are needed, so that leakage-free sealing of the sensor to the outside is possible, and that a constantly stable, reproducible measured signal is obtained because of the defined and narrow electrolyte film on the surface of the measuring electrode.