Objective: Testicular torsion is a common urological complication mostly affecting adolescents and young men. In this study we investigated biochemical and immunohistochemical effects of gallic acid on the damage induced by testicular torsion-detorsion. Study Design: Forty male rats were divided into 4 groups of 10 animals each: control, torsion, torsion/detorsion, and torsion/detorsion+gallic acid. Testicles were removed from the scrotum, and 2.5-hour ischemia was applied to the left testis by twisting the spermatic cord 720° clockwise. Then 3-hour reperfusion was allowed for detorsion. Gallic acid 20 mg/kg was orally administered to the torsion/detorsion+gallic acid group before reperfusion. Biochemical parameters of testicular tissue (MDA, SOD, CAT, and GSH levels) were measured. Testicular tissues were immune-stained with caspase-3 and TNF-a antibody. Results: MDA levels in the torsion/detorsion+gallic acid group were close to those in the control group; however, it was higher in the torsion/detorsion group as compared to the control group. Compared to control group, SOD, CAT, and GSH activities were significantly increased in the torsion/detorsion+gallic acid group. However, those values were decreased in the torsion-detorsion group. Spermatogenic cells and interstitial cells showed positive caspase-3 expression in the torsion and torsion-detorsion groups; however, expression level was decreased in the torsion/detorsion+gallic acid group. TNF-a expression was observed in degenerated spermatogonia, Leydig cells, and macrophages in the torsion and torsion-detorsion groups. In the torsion/detorsion+gallic acid group, TNF-a expression was observed in some interstitial region rather than in cells of seminiferous tubules. Conclusion: Gallic acid treatment could be an alternative therapy in testicular ischemia-reperfusion injury to decrease inflammation, germ cell degeneration, and apoptosis. © The Author(s), 2021.