Objective: To determine the antioxidant status of females with polycystic ovarian syndrome.Methods: Blood samples of 85 females (45 newly diagnosed polycystic ovarian syndrome patients and 40 apparently healthy subjects) between 25 and 45 years of age were obtained from Ekiti State University Teaching Hospital, Ado Ekiti, Ekiti State, Nigeria. Spectrophotometry was used to evaluate the plasma concentrations of malondialdehyde, vitamin A, C and E, reduced glutathione and activities of glutathione peroxidase, catalase and superoxide dismutase. Results: The concentrations of malondialdehyde and glutathione peroxidase activity significantly increased (P<0.05) in patients with polycystic ovarian syndrome compared with the healthy controls, while concentrations of reduced glutathione, vitamins A, C, E and activities of catalase and superoxide dismutase of patients with polycystic ovarian syndrome showed significant decrease (P<0.05) compared to the healthy controls. This study showed that oxidative stress may assume a role in the pathogenesis of polycystic ovarian syndrome. There were significant negative correlations between malondialdehyde and superoxide dismutase, catalase (P<0.01) and vitamin A (P<0.05), while there was a significant positive correlation (P<0.01) between malondialdehyde and glutathione peroxidase. In addition, vitamins A (P<0.05), C (P<0.01) and E (P<0.01) showed significant positive correlations with catalase antioxidant enzyme. However, vitamins C and E showed significant positive correlation (P<0.05) among each other. Conclusions: The involvement of antioxidants in the management of polycystic ovarian syndrome may be helpful as secondary therapy to prevent oxidative damage and may be used as a potential approach to overcome metabolic as well as reproductive disorders associated with infertility in polycystic ovarian syndrome.