Chemical compositions of essential oils obtained by hydrodistillation and microwave extraction systems from sage (Salvia fruticosa Mill.), rosemary (Rosmarinus officinalis L.), basil (Ocimum basilicum L.), summer savory (Satureja hortensis L.), winter savory (Satureja thymbra L.) and mint (Mentha spicata L.) were determined with gas chromatography and gas chromatography-mass spectrometry. Carvacrol (38.72 and 34.03%), thymol (17.15 and 14.36%) and p-cymene (12.26 and 18.32%) were determined in high concentrations in the savory oil extracted by both microwave and hydrodistillation extraction systems. The most important ones for rosemary were 1,8-cineole, camphene and borneol. The main components of essential oil of sage obtained by both methods were 52.96 and 51.25% 1,8-cineole, 3.11 and 4.41% alfa-pinene. The major components in essential oil of mint were determined as 80.63 and 68.46% carvone, in decreasing order. The dominant components of essential oil of basil obtained by both microwave distillation or clevenger distillation method were; 30.44 and 34.90% linalool, 25.48 and 31.40% methyl chavicol, and 19.31 and 13.19% (E)-methyl cinnamate. The major components of Satureja hortensis were identified as p-cymene (10.95 and 19.93%), γ-terpinene (8.33 and 20.53%) and carvacrol (59.35 and 38.83%). © 2011 Wiley Periodicals, Inc.