Abstract The essential oil obtained from the leaves of Campomanesia sessiliflora (Myrtaceae) collected in the Mato Grosso do Sul in the vegetative stage was analyzed by GC and GC/MS. Thirty-nine components were identified in the leaf oil. The major constituents in the leaf oil were bicyclogermacrene (22.4%), spathulenol (15.9%) and germacrene D (14.6%).