Sulfur has been used as a general physical strengthening agent from ancient times in Asia. On the basis of this point, we measured spermatogenic effect of sulfur and methyl sulfonyl methane (MSM) which is used a functional food for arthritis in rats. MSM, a kind of organic sulfur, is used as an alternative of sulfur by some people. Sulfur was administered as a dietary supplement and MSM was administered orally as a solution to 7 week old rat for 6 weeks. All sulfur administered groups showed a significant dose dependent increase in the number of sperm in the testes compared with the control group. Moreover, a histological examination showed an apparent increase in the number of seminiferous tubular cell layers in the testes of the sulfur treated rats. However, there were no observed any increase of sperm in MSM dosing group. In sulfur treated rats, the weights of body, liver, spleen, kidney, testes and epididymides didn`t show significantly differences compared with the control. Histopathological examination was not revealed any morphological change in the liver, spleen and kidney. Thus, sulfur may be effectively used to treat sperm deficiency of men, but not MSM.