Abstract Chemical composition of the essential oil hydrodistilled from the Artemisia lobelii All., after a storage period of seven years, was studied by GC and GC/MS and compared with the chemical composition of the oil obtained right after drying the same plant material. Although two leading constituents of the compared oils were camphor and 1,8-cineole (36.6% and 17.9% in the oil distilled directly after plant material drying and 17.8% and 11.0% in the oil obtained after prolonged storage, respectively), significant decrease in the oil yield (from 0.17% to 0.09%) and increase in the number of components (from 26 to 120) during plant material storage was observed. These changes in the oil content and composition are most probably influenced by the evaporation of the volatile constituents from the plant material during storage, and by the chemical transformations of the plant native metabolites. Key Word Index: Artemisia lobelii Asteraceaeessential oil composition1,8-cineolecamphorstorage effects