The present disclosure provides a gas chromatography-ion mobility spectrometry apparatus, including a housing, an injection port mounted to and connected with the housing and configured for input of a gas containing a sample therein, a multicapillary column configured for separation of a gas substance and an ion mobility tub configured for analysis of the gas substance. The gas chromatography-ion mobility spectrometry apparatus further includes: a gas path part connected with the ion mobility tube and configured for providing the gas to the ion mobility tube and receiving a gas discharged from the ion mobility tube; and a buffer base part detachably mounted to the housing and configured to isolation vibration outside the buffer base part, the ion mobility tube being disposed on the buffer base part, wherein the gas path part is mounted in an interior space of the buffer base part.