Abstract: The aims of this study was to analyze the chemical composition of fruits and stem volatile oils of Olea europaea L. cv. Chemchali and to test the efficacy of volatile oils against four pathogenic bacteria and four phytopathogen strains and their antioxidant activity. The GC-MS analysis revealed 38 compounds representing 88.5 and 73.6% of the total oils containing 3-ethenylpyridine (12.5%), (E)-2-decenal (11.4%) and 2-ethylbenzaldehyde (7.7%) in fruit and nonanal (9.9%), (E)-2-decenal (9.6%) and benzyl alcohol (9.00%) in stem as major components, respectively. The antibacterial and antifungal activities of stem volatile oils were relatively good. Therefore, the stem of Olea europaea L. demonstrated higher activities against tested fungi and bacteria than the fruit. The DPPH and ABTS-radical-scavenging activities of the oils showed that the lowest EC50 value was detected in volatile oil from fruit.