Abstract The chemical composition of the essential oils obtained from the leaves of Piper peltata (L.) Miq. and P. aduncum L. from Cuba were examined by combined GC/MS. The oil obtained from P. peltatum was characterized by the presence of caryophyllene oxide (22.9%), spathulenol (9.0%), trans-calamenene (5.4%) and Î±-copaene (5.2%) as major constituents, while that of P. aduncum contained dillapiole (82.2%) as the major component.