The purpose of this study was to examine potential long-term post-torsion changes that can occur in the histopathology, biochemistry and spermatogenesis of both torsioned and nontorsioned opposite testes. The study also determines the effect of zinc (Zn) administration on the testicular torsion/detorsion (T/D) damage on both testes. Forty-eight male rats, divided equally into eight groups: (SHAM), (SHAM+,Zn+), (T/D+, Zn- 1 month), (T/D+, Zn- 2 months), (T/D+, Zn- 3 months), (T/D+, Zn+ 1 months), (T/D+, Zn+ 2 months), (T/D+, Zn+ 3 months), have been used. Drug administration was carried out by adding 100 mu g (0.016 ml/rat) Zn per rat to drinking water in related groups. Testicular damage decreased superoxide dismutase (SOD) and glutathione (GSH) and increased malondialdehyde (MDA) in the testis tissues of rats, while Zn administration increased SOD and GSH and decreased MDA in the testis tissues in comparison with the SHAM group. The beneficial effect of zinc sulphate was more evident on the nonrotated testis than the rotated testis. In the histopathological study, a significant decrease in torsion and detorsion injuries was observed in the treatment groups compared to the torsion and detorsion groups. We found a protective effect of zinc sulphate on oxidative stress as a result of T/D injuries in rats, especially for the nonrotated testis; results were supported histopathologically.