In this study, the fatty acid compositions of Turkish virgin olive oils produced in the Izmir province, an important olive production region of Turkey, were classified by chemometric methods: principal component analysis (PCA) and discriminant analysis (DA). A total of 103 oil samples were examined over the course of two harvest years (2001-2002 and 2002-2003). The samples were divided into five groups according to olive growing zones: North (Ayvalik cultivar), East (Memeli, Memecik, Domat and Gemlik cultivars), South (Memecik cultivar), Izmir Penisula (Erkence cultivar) and Firms (poly-varietial oils or commercial blends). Consistent with discriminant analysis (DA), the predicted grouping in terms of the two harvest years were correctly separated as 84.6 and 85.9%, respectively. The highest levels of predicted grouping for the two harvest years were found in the North (Ayvalik cultivar) and Izmir peninsula (Erkence cultivar) groups (as 100%). In addition to oleic, linoleic, linolenic, margaric and margoleic acids, total trans isomers of linoleic, linolenic and palmitic/linoleic were determined to be the best descriptive components for the oil samples.