Abstract: Objective:To investigate the effects of vitamin E on sperm quality of rats exposed to high pressure in diving.Methods:A total of 16 male rats were randomly divided into solvent control group and vitamin E group according to the random number table method,with 8 rats in each group. Before exposing to high pressure,the vitamin E group was given 100 mg·kg -1·d -1 of vitamin E by gavage,while the solvent control group was given the same amount of corn oil by gavage. The rats in both groups were exposed to air diving at a depth of 60 meters for 1 hour each time for 30 consecutive days,and were sacrificed immediately after the last exposure. The morphology of rat testis was observed by HE staining. The density and motility of rat sperms were observed under a microscope,and the DNA fragmentation index(DFI)of rat sperms was detected by flow cytometry. Results:Compared with the solvent control group,there was no significant changes in testicular morphology or sperm density in the vitamin E group( P>0.05);while the sperm motility and DFI in the vitamin E group were much better than those in the solvent control group,and the differences were statistically significant( P<0.05). Conclusion:Vitamin E can effectively prevent DNA damage and sperm motility decline in male rats exposed to high pressure in diving.