A study was made to investigate if monovarietal olive oils may be differentiated by their chem. compn. Long-chain alcs., triterpenes and fatty acids were detd. by GC in six Italian olive cultivars, Coratina and Provenzale from Puglia, Frantoio and Moraiolo from Toscana, Bosana from Sardegna and Dritta from Abruzzo. Basic statistics and multivariate methods were first applied to the GC data of each class of compds. and then to the complete set of data with the aim of obtaining a clear discrimination of the cultivars. When Principal Components Anal. (PCA) was applied to the whole set of data consisting of alcs., triterpenes and acids, the PCA revealed that the compds. (variables) that gave the better class distinction were: cycloartenol for Coratina, acids C20:0 C17:0, C18:0 for Dritta, citrostadienol for Frantoio and b-sitosterol for Moraiolo. Bosana and Provenzale correlated with erythrodiol and uvaol. A correct assignment of each oil sample to its monovarietal group was obtained.