In this study, the fatty acid compositions of Turkish virgin olive oils produced in the Aegean region, the major olive production zone of Turkey, were classified by chemometric methods: Principal Component Analysis (PCA) and Discriminant Analysis (DA). A total of 268 oil samples were examined over the course of two harvest years (2001-2002 and 2002-2003). The samples were divided into six groups according to the olive growing zones: Edremit Gulf (Ayvalik cultivar), Izmir province (AyvalA +/- k, Memeli, Memecik and Gemlik), AydA +/- n province (Memecik, Manzanilla and Gemlik), Mugla (Memecik), Manisa (Gemlik, Domat, Uslu, AyvalA +/- k), A degrees zmir Peninsula (Erkence cultivar) and Firms (poly-cultivar or commercial blends). Consistent with discriminant analysis (DA), the predicted grouping in terms of the two harvest years were correctly separated as 74.5 and 74.8%, respectively. The highest levels of predicted grouping for the two harvest years were found in the Edremit Gulf (AyvalA +/- k cultivar), Mugla province (Memecik cultivar) and A degrees zmir peninsula (Erkence cultivar) groups (as 90-100%). In addition to oleic, linoleic, linolenic, margaric, margoleic, total trans isomers of linoleic, oleic/linoleic and palmitic/linoleic were determined to be the best descriptive components for the oil samples.