Abstract: Volatile components was extracted from Tylophora ovata (Lindl.) Hook.ex Steud.by supercritical CO2 fluid extraction. Extraction conditions were: extracting 3 h at 50 ℃, 35 MPa (pressure) and using 20 ml 95 % alcohol as modifier. The volatile components extracted were determined by gas chromatography with area normalization method and identified by gas chromatog- raphy mass spectrometry(GC-MS).The optimal chromatographic conditions were: HP-5 MSsilica capillary column (0.25 mm× 30 m×0.25μm); column temperature: 60℃( hold for 1 min) to 280 ℃ at a rate of 4 ℃/min, and hold for 10 min;split injection, 20:1; injector temperature 250 ℃. Thirty nine components were identified for the constituents extracted by SFE CO2.

Key words: supercritical CO2 fluid extraction, gas chromatography-mass spectrometry (GC-MS), Tylophora ovata (Lindl.) Hook.ex Steud