The aim of this study was to investigate potential therapeutic efficiency of ozone therapy in the treatment of experimental endometriosis in rats. Fifteen rats were divided into three groups, which were labeled as the (1) sham control, (2) the ozone (treated with intraperitoneal ozone-oxygen mixture) and (3) the GnRH-agonist (given single dose (1 mg) leuprolide acetate depot formulation) group. Endometrial implant activity of superoxide dismutase (SOD), malondialdehyde (MDA), interleukin-1 beta (IL-1 beta), IL-6, tumor necrosis factor-alpha (TNF-alpha), and vasculary endothelial growth factor (VEGF) were measured after ozone-therapy. Furthermore, peritoneal fluid activity of SOD, MDA, and TNF-alpha were also measured before and after ozone-therapy. Serum AMH levels of the rats those were given ozone-therapy and control groups were measured. The rats given ozone-therapy showed significantly reduced endometriotic implant volumes. After ozone-therapy, a significant increase in activity of SOD in peritoneal fluid was detected. Conversely, implant levels of SOD in rats given ozone therapy was found to be significantly decreased. Both peritoneal fluid and implant levels of MDA were significantly decreased after ozone-therapy. Implant levels of TNF-alpha, IL-1 beta, and IL-6 were significantly increased following ozone-therapy. VEGF levels of implant was found to be unchanged after ozone-therapy. Serum AMH levels of animals were given ozone-therapy and control groups were similar. The number of both primordial and preantral follicles were significantly decreased after ozone-therapy. However, the number of atretic follicles were similar in ozone-therapy and control groups. Repeated administration of ozone-oxygen therapy in non-toxic doses inhibits growth of endometrial implants.