The purpose of this study was to evaluate the effect of the addition of Origanum vulgare extract to in vitro capacitation sperm medium (IVCSM). This study investigated the antioxidant and antimicrobial effects of O. vulgare extracts at different concentrations (0.3, 0.6, 1.2 μg/ml and 25.0, 50.0, 100.0 μg/ml, respectively) in IVCSM. Significant enhancements in semen quality parameters such as total motility, live and live capacitated sperm were found when O. vulgare extract was added as an antioxidant source (1.2 μg/ml). The treatment of spermatozoa with O. vulgare extract at the highest concentration (100 μg/ml) for 2 hrs without antibiotics improved sperm characteristics. In conclusion, incubation of sperm with O. vulgare extract in capacitation medium had beneficial effects on the characteristics of ram sperm.