Oolong is a traditional Chinese tea produced through a process including withering the tea leaves and oxidation before curling and twisting. There are some varieties of tea products with different flavours based on the degree of oxidation. In this study, the volatile components from some oolong tea products were obtained by hydro-distillation using Clevenger type apparatus combined with solvent extraction method, and then analyzed by GC-MS. These results showed that the main volatile components of these studied tea products were (Z)-linalool oxide, (E)-linalool oxide, linalool, epoxylinalol, 3,7-dimethyl-1,5,7-octatrien-3-ol, (E)-geraniol, nerolidol, (Z)-2-penten-1-ol, furfural, phytol… These tea products were also classified into 3 groups based on the volatile composition in the obtained essential oil.