Artemisia austro-yunnanensis, belonging to the family Asterales, is distributed mainly in south Asia regions. So far, there is no chemical and biologically active researches about this plant. In current study, for the first time, essential oil from the the flowers of Artemisia austro-yunnanensis was extracted by hydrodistillation and analyzed by gas chromatography (GC) and GC/mass spectrometry (GC-MS). The main compositions were Humulane-1,6-dien-3-ol (16.52 %), 3,3,6-Trimethyl-1,5-heptadien -4-ol (7.36 %), Agarospirol (6.10 %), Caryophyllene oxide (6.05 %), Borneol (3.34 %) and β-Bisabolo (3.00 %). And the antioxidant activity of the essential oil from that plant was evaluated by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay.