The chemical compositions of 15 commercial samples of essential oils of leaves of Myrtus communis L. from five different Mediterranean locations (Corsica, Morocco, Tunisia, Lebanon, and former Yugoslavia) were studied. Forty-seven compounds were identified by GUMS. They could be divided into two groups on the basis of their percentages of a-pinene; over 50% (Corsica and Tunisia), and under 35% (the others). The percentages of limonene, 1,8-cineole and myrtenyl acetate were consistent with this classification. The chemical compositions of these oils can be compared to those of Spanish oils.