The present invention relates to a gas sensor (1) for detecting gases, with at least one gas-sensitive layer which is applied to a substrate (2), wherein at least one conductor track (3) for contact-connecting the layer is also provided on the substrate (2), and wherein the conductor track (3) is formed from a doped metal oxide material with non-catalytic properties in order to avoid the conductor track (3) influencing the detection of the gas. This avoids the disadvantages of the prior art and provides contact-connection of the gas-sensitive layers which does not influence the sensitive properties when detecting the gas by means of the layer.