A gas-measuring system is provided that is suitable for both mobile and stationary use. A mobile measuring device (2) with sensors (4, 5, 6, 7) for detecting gas concentrations and a base station (3) are provided for this purpose. The mobile measuring device (2) is inserted into a holder (31) of the base station (3) and the operating functions to the measuring device (2) are now switched over to the base station (3).