An electrochemical gas sensor with a plurality of electrodes is provided with an electrolyte, with a gas-permeable membrane (1), with a gas-permeable and conductive carrier layer (2) applied to the membrane (1) and with at least one measuring electrode (3) applied to the carrier layer (2). The measuring electrode (3) is of a punctiform design and the electrochemical potential difference of the reaction between the carrier layer (2) and the measuring electrode (3) is at least 20 mV, can be manufactured in a compact form and makes possible an especially low power consumption for measured gases in the percentage range.