Abstract: Chromatography (SFC) and GC/MS have been developed in this paper. The data showed (1) using a mobile phase of carbon dioxide modified with 5% methanol ,SFC achieved excellent result, and the time for the analysis was less than 3 minutes; (2) using GC/MS, the analysis was finished within 7 minutes. The two methods could be used to determine caffeine in tea rapidly. The other components contained in tea did not interfere the assay.

Key words: SFC (Supercritical Fluid Chromatography), GC/MS, tea, caffeine