Background: Achillea eriophora is an important species of Achillea that is native (Endemic) in Iran. It grows exclusively in the South provinces of Iran especially “Fars” province. It contains higher level of essential oil in comparison to other species. Objective: Study on the essential oil composition of Achillea eriophora DC. in wild conditions and comparison to field condition. Methods: Top flowering part of the Achillea eriophora wild population was collected from “Jahrom” (“Mohammad Abad” village in 10th Km of the South-East of “Jahrom”) in the South of “Fars” province on June 2006. The essential oils of the samples were extracted by “Clevenger” apparatus and its constituents determined by GC and GC-MS. Also, the seeds of this plant also cultivated in September 2006 in Mashhad region. On July 2007, top flowering parts of the cultivated plants harvested at full flowering stage. After drying, essential oils content of the samples determined and its components detected as mentioned for wild samples. Results: The essential oils content of the wild and cultivated samples were 2 % and 2.25% v/w respectively. In wild samples thirty components were identified and the major components were: Camphor (30.4%), 1,8-Cineole (25.24%), Camphene (6.21%)، α-Pinene (4.49%) and Myrcene (3.91%). Thirty-six components determined in the cultivated samples and the main components were: Camphor (28.98%), 1,8-Cineole (26.98%), Camphene (5.98%) and α-Pinene (4.23%). Conclusion: In cultivated samples, essential oil content and constituents increased but the relative content of the main constituents decreased.