Arsenic causes lipid peroxidation leading to alterations in antioxidant status in organisms. In this study, the reproductive effects of chronic exposure to arsenic and the protective effects of polydatin (PD) were evaluated in 35 Wistar male rats, which were divided equally into five groups. The control group received a normal diet and tap water, arsenic (100 mg l⁻¹, approximately 1/50 of oral LD₅₀) was given via drinking water to experimental groups except control group, and PD was orally given to the other groups at dose of 50, 100 and 200 mg kg⁻¹ for 60 days. Arsenic administration decreased sperm motility, glutathione level, superoxide dismutase and catalase activities in testicular tissue of rats. In contrast, malondialdehyde level and DNA damage were found to be high levels in arsenic‐treated group. Histopathologically, it was observed that decreased sperm concentration and degeneration of Sertoli cells in testicular tissue. PD administration, partially 200 mg kg⁻¹, reversed arsenic‐induced lipid peroxidation, DNA damage, antioxidant enzyme activity and cell integrity in testis of rats. These results demonstrate that PD decreases arsenic‐induced lipid peroxidation, enhances the antioxidant defence mechanism and regenerates tissue damage in testis of rats.