Objective: To study the protective effects of Potentilla fulgens extract on damage of testicular tissue created by ischemia and reperfusion treatment via histopathological, immunohistochemical, and TUNEL experiments. STUDY DESIGN: In this study 24 Sprague-Dawley male rats were divided into 4 subgroups: control group, torsion group, torsion-detorsion group, and Potentilla fulgens+torsion-detorsion group. The extract of Potentilla fulgens was intraperitoneally injected into the rats, 400 mg/kg for 5 days. The right testicle was exposed to torsion and detorsion for 2 hours with a 720° turn. The right testicle was dissected from the scrotum after the rats were anesthetized with ketamine hydroxide. Following fixation of 10% formaldehyde solution, routine tissue processing protocol was applied. Immunohistochemically slides were stained with TNF-α antibody. Apoptotic changes were examined using the TUNEL protocol. Results: In this study seminiferous tubule diameter and depth of spermatic cells were compared among the experimental and control groups. Histopathologic examination shows that degeneration and disorganization of the spermatic cells and changes in tubule diameter were found to be statistically significant. In addition, histopathological examination of the apoptotic indices was scored using the TUNEL method. Immunohistochemically, TNF-α expression was positively observed in the ischemia and the ischemia-reperfusion groups. Conclusion: As a result of torsion and detorsion exposure, which led to damage in spermatic cells of seminiferous tubules, Potentilla fulgens was shown to decrease apoptotic development and was thought to be the cause of activation in spermatic cells. © Science Printers and Publishers, Inc.