By combination of liquid-solid chromatography, capillary GLC and mass spectrometry, the essential oil obtained by steam distillation from the leaves and flowers of ARTEMISIA COERULESCENS L., growing in Tuscany (Poggio di Monselvoli, Siena), was analysed, alpha-Thujone, beta-thujone and camphor accounted for about 69% of the oil which contained more than a hundred compounds, most of which were present only in traces; 36 components were identified.