The volatile compounds were extracted in the different parts of Herba Erigerontis Annui by microwave-assisted headspace solid-phase micro-extraction(MAE-HS-SPME). Their constituents were analyzed and identified by gas chromatography-mass spectrometry combined with Kovats retention index, The results showed that 67,69 and 69 volatile constituents in the stem, in the leaf and in the flower of Herba Erigerontis Annui were separated and identified. Accounting for 92.71%, 96.72% and 96.16% of the total peak areas, respectively. Which is the main component in stem β-Elemene (5.22%), germacrene d (41.80%) and( )-β- selinene (7.71%).And in the leaves cyclotene (6.43%),β-Elemene (8.45%), germacrene d (40.17%) and (E,E)-α- Farnesene(5.80%).And in the Flowers cyclotene (4.20%), β-Elemene (8.65%) and germacrene d (31.20%).It was also observed that there were significant differences in the relative contents of three parts.