The constituents of essential oils isolated by hydrodistillation of the overground parts of Ocimum basilicum L. and Ocimum minimum L. from Turkey were examined by GC-MS. A total of 49 and 41 components, respectively, were identified accounting for 88.1% and 74.4% of the oils of O. basilicum and O. minimum, respectively. The oil of O. basilicum contained, as main components, methyl eugenol (78.02%), Î±-cubebene (6.17%), nerol (0.83%) and Îµ-muurolene (0.74%). Major compounds in the volatile oil of O. minimum were geranyl acetate (69.48%), terpinen-4-ol (2.35%) and octan-3-yl-acetate (0.72%). The essential oil of O. basilicum was characterised by its high content of methyl eugenol (78.02%), whereas the most important essential oil constituent of O. minimum was geranyl acetate (69.48%).