The aim of the present study was to clarify the effects of silymarin on experimental testicular ischemia / reperfusion injury. A total of 40 Wistar albino rats (10-12 weeks of age weighing 280-300 grams) were randomly divided into five groups.Control group: No surgical procedures were performed. Torsion 3 h / detorsion 3 h group; torsion 3 h / detorsion 24 h group; torsion 3 h / detorsion 3 h + silymarin (250 mg/kg) group; and torsion 3 h / detorsion 24 h + silymarin (250 mg/kg) group. In the study, 720 ° torsion was applied to the left testicle. At the end of the study, blood was collected from the rats and an orchiectomy was performed on the left testicles. It was found that tumor necrosis factor alpha (Tnf-α) and 8-hydroxy-2-deoxyguanosine (8-OHdG) expression levels in testicular tissue increased significantly in torsion/detorsion groups, and the expression levels decreased significantly with silymarin administration. In addition, in the testicular tissue of the torsion/detorsion groups, glutathione (GSH) levels, superoxide dismutase (SOD), and glutathione peroxidase (GPx) activities decreased, while malondialdehyde (MDA) levels increased. It was found that the parameters specified were reversed with the administration of silymarin. Based on our findings, we can say that silymarin reduces testicular injury by activating antioxidant mechanisms in ischemia/reperfusion injury and minimizing the inflammatory response.