Nabali Baladi , Nabali Mohassan and Souri are the predominant olive cultivars in Palestine. In order to investigate morphological intercultivar variability, samples were taken from leaves, flowers, fruits and stones from trees of the three cultivars. Oil was also extracted from fruits of the three cultivars for biochemical analysis. Notable significant differences among the cultivars were observed in all characteristics considered, including; tree canopy, leaves, inflorescence and fruit characterstics. The acidity, peroxide number and the spectrophotometer absorbencies in ultra-violet were low of the oils of the three cultivars. Most cultivars had an oleic content of about 60% or higher except for the 'Nabali Mohassan'. The sterol composition and content were quite different in the three cultivars. The 'Nabali Baladi' had a relatively high value of Δ- 7stigmastenol. All of the biochemical values (acidity, peroxide number, absorbencies in ultra-violet, fatty acid composition, sterol composition and content) used to evaluate oil quality were within the IOC trade standards.