Tramadol hydrochloride, a centrally-active synthetic opioid analgesic, is used extensively in Egypt and Middle East countries. The present study was designed to investigate the dramatic effects of tramadol administration on ovarian tissues focusing on gonadal function, oxidative stress, apoptosis and histological changes. Thirty female albino rats, used in the current study, were divided into three groups; a control group and 30 and 60 mg/kg body weight tramadol-treated groups. Tramadol intubation resulted in a significant decrease in the serum levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH), progesterone (Pg) and estradiol (E2), whilst a significant increase in the level of prolactin (PRL) was shown when compared to the control group. Ovarian malondialdehyde (MDA) and nitric oxide (NO) levels showed a significant elevation with both tramadol tested doses concomitant with a significant up-regulation of ovarian inducible nitric oxide synthase (iNOS) mRNA as compared to the control rats. A significant reduction in the activities of reduced glutathione (GSH), superoxide dismutase (SOD) and glutathione peroxidase (GPx) together with down-regulation of SOD and GPx mRNA expression was observed in the ovary of tramadol-administered rats. Consistently, mRNA and protein expression level of proapoptotic (p53 & Bax) marker showed a significant up-regulation, whereas the anti-apoptotic (Bcl-2) level was significantly down-regulated in ovarian tissues of tramadol-intubated groups. Heat shock protein 70 (Hsp70) expression level was significantly elevated in ovarian tissues of tramadol-treated rats. The obtained biochemical and molecular findings were further confirmed by the histopathological data that showed obvious deterioration, degeneration and necrosis of ovarian follicles in tramadol-administered rats. Thus, tramadol intubation affects the ovarian function. Therefore, females that treated with long-term tramadol therapy should be screened routinely for symptoms of hypogonadism.