Volatile compounds in rhizomes of cyperus rotundus L.have been proven to be pharmacologically for its clinical use and have been used as the basis of its quality evaluation.A novel solid-phase extraction element named "magic chemisorber" (MC) combined with thermal desorption-gas chromatography/mass spectrometry (TD-GC/MS) using a pyrolysis-GC system was applied for the analysis of volatile compounds in cyperus rotundus L..The MC consists of a titanium (Ti) tubing (30 mm × 1.2 mm i.d.× 1.6 mm o.d.), whose inner and outer surface are deactivated and bonded with the same length of PDMS tube.The thick layer of PDMS is 0.5 mm (70μ1).