Abstract:The chemica1 constituents of 171essential oil samples of Artemisia L. in China were analysed and 305 compounds were identified. In the samples analysed , 64 species were included and 47 of which were from the sections of Subgen. Artemisia and the rest were from the sections of Sub gen. Dracomcubre (Bess. ) Peterm. According to the analyses, there is a regularity for the distribution of these compounds in above two subgenera. The major constituents of the essential oils from Subgen . Artemisia are monoterpenoids and sesquiterpenoids, while that from Subgen. Dracumculus (Bess. ) Peterm. are sesquiterpenoids and aromatic compounds. It means that the distribution of chemical constituents is correlated with the classification of Artemisia L. , in which the species from more primitive to advanced can be divid ed into 7 sections as follows. Subgen. Artemisia: Sect. Absinthium DC. (monoterpenoids) - Sect. Abrotanum Bess. ( monoterpenords ) - Sect. Artemisia (monoterpenoids) - Sect. Viscidipubes Y. R. Ling (monoterpenoids and sesquiterpenoids)-Sect. Albibractea Y. R. Ling (sesquiterpenoids). Subgen, Drameulus (Bess. ) Peterm. : Sect. Dracunculus Bess, (sesquiterpenoids and aro matic compounds)-Sect. Latilobus Y. R. Ling (sesquiterpenoids and aromatic compounds).