Objective: To analyze the main chemical components of essential oil from Aqeratum conyzoides by supercritical CO2 fluid extraction(SFE). Method: The essential Oil from A. conyzoides was extracted by SFE

and the chemical components was analyzed by gas chromatography and mass spectrometry(GC-MS)

then the relative content of each component was determined by area normalization. Result: Sixty components

95.96％ of the total oils had been identified

and the main components were 3-(4-methoxyphenyl)-2-propenoic acid ethyl ester(12.78%)

eucalyptol(11.59%)

1R-α-pinene(8.52%)

(+)-2-bornanone(5.03%)

3-(1-formyl-3

4-methylenedioxy)methyl benzoate(4.24%)

L-verbenone (3.52%)

caryophyllene(3.33%)

L-borneol(3.14％).The main components were extremely different from the essential oil extracted by team distillation(SD). Conclusion: The present experiments provided a scientific basis for the integrated utilization of A. conyzoides.