Abstract: Objective: Studies on the effects of infrared rays radiation on the testicles in rats. Methods: By using different wave infra-red rays radiation on the testicles in rats,Study the testosterone of differentgroup,pregnancy rate of matching female rats and the light structure of testicles. Results: There is not significant difference with testosterone of every group（P＞0.05）;The pregnancy rates of matching female rats with different wave infra-red rays radiation are obvious lower than the control group.The pregnancy rate of IRB group is lowest;The rats’ tubulus seminiferi contorti of test groups were damaged,particular the group of IRB.They can recover after 4 weeks. Conclusion: Infra-red radiation could have an effect on the testicles in rats.