The utility model discloses a gas sampling device which comprises a shell, two semipermeable membranes and a gas tube, wherein the two semipermeable membranes are arranged parallel to each other and are connected through the shell, then an independent space is formed among the two semipermeable membranes and the shell; the gas tube is connected to the independent space through the shell; because of the apertures of the semipermeable membranes, gas molecules can permeate but water molecules cannot permeate. By adopting the technical scheme, a sample gas is high in sampling efficiency, fast in reaction speed, small in environment change influence, convenient and safe to use and capable of being well applicable to requirements of continuous rapid chromatographic analyzers. The gas sampling device disclosed by the utility model is convenient and safe to use, and can be well applicable to requirements of continuous rapid chromatographic analyzers.