Abstract: 【Objective】To purify and identify the allelopathic substances from Artemisia annua extract.【Methods】The experiment used purified water as a solvent to extract chemical components from the roots,stems,and leaves of Artemisia annua,and quantitatively determined the acidic,neutral,and alkaline components using GC-MS.【Results】Different substances were detected in different parts of Artemisia annua extract,among which 38 acidic components were detected,roots contained the most types（20 types）;There were 21 neutral components,stems contained the most types（10 types）;There were 21 alkaline components,leaves contained the most types（9 types）. The roots and stems contain a significant amount of organic acids and alkenes,such as 5-（1-methylethylene）-1,3-cyclopentadiene,2,3-dioxodiacetylbutyronitrile,and cisbicyclo[4.2.0] octan-3,7-diene.【Conclusion】The roots and stems of Artemisia annua may be the main sites for the production of allelopathic substances,with products mostly consisting of organic acids and alkenes.

Key words: Artemisia annua, Allelopathic substance, Purification and identification