Some of the Lavandula L. species are well-known for their valuable essential oils which are widely used in cosmetic, perfumery, pharmaceutical and food industries. The aim of this study was to analysis both the essential oil content and quality changes of lavender (Lavandula angustifolia), lavandin (Lavandula × intermedia) and French lavender (Lavandula stoechas) which are grown under Afyonkarahisar conditions in Turkey. The essential oil of L. angustifolia, L. × intermedia and L. stoechas obtained by hydro-distillation. The essential oil content of flowerheads samples were 3.33, 5.20 and 0.94 % (v/w) respectively. The essential oil analysis of plants were carried out by gas chromatography-mass spectrometry (GC-MS). 37 compounds with representing 100 % were identified for lavender including 1,8-Cineole (59.446 %) as the most major compound and α-Pinene, β-Pinene, dl-Limonene, Camphor, Linalool, δ-Terpineol, 4-Ethyl-2-hexynal, α-Terpineol, Borneol, Caryophyllene oxide, Levomenol as the other major ingredients. The most major composition of lavandin was identified Linalool (45.657 %) and other main compounds were Linalyl acetate, 1,8-Cineole, cis-Ocimene, trans-β-Ocimene, Camphor, Lavandulyl acetate, δ-Terpineol, δ-Terpineol, Borneol, Neryl acetate, Geranyl acetate, Geraniol and Levomenol with 28 compounds and representing 99.73 %. Also, according the results, the most major compounds of French lavender oil were Camphor (38.382 %) and Fenchone (32.212 %). 1,8-Cineole, (-)-Bornyl acetate, trans-Verbenol, (-)-Myrtenyl acetate, Veridiflorol, 18-Crown-6 and Isothiazole,4,5-dimethyl- were the other components with 39 compounds and representing 100 %. The results showed that essential oil content and secondary metabolites of lavender and lavandin were more valuable than French lavender.