The aim of this study was to investigate the protective effect of Ginkgo biloba (EGb 761) on testicular torsion/detorsion induced ischemia-reperfusion (I/R) injury. A total of 24 male Wistar albino rats were divided into three groups: control, I/R and I/R treated with EGb 761: each group contains 8 animals. Testicular torsion was created by rotating the left testis 720 in a clockwise direction. The ischemia period was 5 h and orchiectomy was performed after 5 h of detorsion. EGb 761 (50 mg/kg, orally) was administrated only once, 40 min prior to detorsion. To date, no more histopathological changes on testicular torsion/detorsion induced ischemia-reperfusion (I/R) injury in rats by EGb 761 treatment have been reported. Spermatogenesis and mean seminiferous tubule diameter (MSTD) were significantly decreased in I/R groups were compared to the control group. Furthermore, EGb 761 treated animals showed an improved histological appearance in I/R group. Our data indicate a significant reduction in the activity of TUNEL and endothelial nitric oxide synthase (eNOS) in testes tissue of I/R treated with EGb 761 therapy. Electron microscopy of the testes of rats demonstrated that EGb 761 pretreatment was particularly effective in preventing the mitochondrial degeneration, dilatation of SER and enlarged intercellular spaces in both Sertoli and spermatid cells in I/R treated animals. We believe that further preclinical research into the utility of EGb 761 may indicate its usefulness as a potential treatment on testes injury after I/R in rats. (C) 2011 Elsevier Inc. All rights reserved.