abstract the rosemary aroma composition and the enanatiomeric ratio of chiral compounds were examined by gc (fid), gc/ms and chiral gc. solid-phase microextraction (spme) was examined for its suitability for isolation of volatiles from the leaves of five samples of rosemary in comparison with the traditional steam distillation procedure. mostly five rosemary aroma components were taken into consideration: 1,8-cineole, camphor, borneol, -terpineol and verbenone. eight pairs of enantiomers were separated in all of the analyzed samples: -pinene, camphene, -pinene, limonene, linalool, camphor, borneol and -terpineol. but only one compound-borneol was detected in all the samples, with the same enantiomeric ratio and high optical purity of the minus form, over 85% of total. spme may be used as a fast and precise tool for measuring the enantiomeric ratio of this compound when authenticity of rosemary aroma is controlled. key word index: rosmarinus officinalis lamiaceaeessential oil composition-pinene1,8-cineolecamphorheadspace volatilesenantiomeric distributionrosemary authenticitys