Ion mobility spectrometry (IMS) is difficult to identify some organic compounds with closed reduced mobility values, such as the isomeric compounds of xylene. A tandem analytical technique, UV photoionization ion mobility spectrometry (UV-IMS) coupled with a packed column gas chromatography (GC), GC-UV-IMS, was developed for the efficient separation and detection of aromatics compounds. The gas chromatograms and ion mobility spectra were measured at different column temperatures and the flows of nitrogen carrier gas in order to obtain optimized experimental parameters. The gaseous mixture of benzene, toluene, o-xylene, m-xylene and p-xylene was detected with a homemade GC-UV-IMS apparatus. The results show that three isomeric compounds o-xylene, m-xylene and p-xylene can not be distinguished when only using the UV photoionization IMS. However, two dimensional gas chromatogram-ion mobility spectrum can greatly enhance resolution of these organic compounds on the basis of their retention time and drift time. This demonstrates that the established GC-UV-IMS has a good ability to discriminate and detect trace volatile organic compounds.