Rosmarinic acid having potential anti-inflammatory and free radical scavenging activity. We examined the chemotherapeutic effect of rosmarinic against cisplatin (CIS)-induced ovarian toxicity via modulation of oxidative stress and inflammation.Swiss BALB mice used in experimental protocol and mice were divided into different groups. Intraperitoneal injection of CIS (7 mg/kg) was used for ovarian cancer induction. The rats were received rosmarinic acid (2.5, 5, and 10 mg/kg, body weight) treatment for 22 weeks. Body weight, ovary weight food, and water intake were estimated at regular time intervals. Hormonal and antioxidant parameters were estimated in the ovary tissue and serum at the end of the study. Cytokines, inflammatory, and apoptosis parameters were determined at the end of the study.Finally, the ovary tissue histopathology was performed at end of the experimental study. Rosmarinic acid significantly (p < 0.001) improved the body weight and reduced the ovary weight. Rosmarinic acid considerably reduced the hormonal assay parameters, such as antimullerian hormone, estradiol, luteinizing hormone, and follicle-stimulating hormone compared to model control mice. Rosmarinic treatment significantly (p < 0.001) reduced the level of nitric oxide, myeloperoxidase, and boosted the level of antioxidant parameters, such as glutathione, superoxide dismutase, catalase, and glutathione peroxidase in serum and ovary tissue. Rosmarinic acid downregulated the cytokines like interleukin-6, tumor necrosis factor-α, interleukin-1β; inflammatory parameter includes prostaglandin E 2 , cyclooxygenase-2, and inducible nitric oxide synthase at a dose-dependently. Ovary tissue histopathology showed improvement after rosmarinic acid treatment. The result suggests that rosmarinic acid is a protective effect in ameliorating CIS-induced ovary toxicity via alteration of inflammatory and apoptosis parameters.