The essential oils of two samples of Blepharocalyx salicifolius (Kunth.) O. Berg growing wild in Bolivia were analyzed to determine their chemical composition. These samples were collected at different periods of the year and although the same products appear in the samples, the relative percentages show an important variation. Mono-oxygenated sesquiterpene molecules, among them ledol and (E)-nerolidol, are the main compounds observed in one sample. In another sample, about two-thirds of the observed compounds are monoterpenes, and more particularly Î²- and Î±-pinenes, 35% and 17%, respectively.