Abstract A hydrodistilled oil from the aerial parts of Eryngium billardieri F. Delaroche was analyzed by a combination of GC and GC/MS. Forty-two components were identified representing more than 97.2% of the oil. The main constituents of the oil were α-muurolene (42.0%), β-gurjunene (17.0%), δ-cadinene (6.2%) and valencene (5.7%). Key Word Index: Eryngium billardieri Umbelliferaeessential oil compositionα-muuroleneβ-gurjuneneδ-cadinenevalencene