Contents of five main components of essential oil in rhizome of Atractylodes lancea(Thunb.) DC.which collected from original regions and introduced in the some habitat of Nanjing for one year,were analyzed by GC.The results showed that main components of essential oil from wild A.lancea in Jiangsu Province were atractylon and atractylodin;those from Hubei Province were hinesol and β-eudesmol;there was an obvious difference in contents and components of essential oil between different locations.The variation was decreased clearly after cultivated in Nanjing.It is concluded that production regions give obvious influences on the compositions of active constituents of essential oil in the rhizome.