Objective：to study the effect of the sea cucumber small molecule peptide on the levels of the serum testosterone of the exercising mice and testicular tissue malondialdehyde（MDA）and superoxide dismutase（SOD）. Methods：30 male KM mice are randomly divided into four groups：the quiet group（C），the aerobic exercise group （T1），aerobic exercise group with small molecules added sea cucumber peptide（T2），anaerobic exercise group（T3） and anaerobic exercise group with sea cucumber small molecule peptide（T4）. T1，T2，T3 and T4 are given treadmill training in different ways. The content of MDA and SOD of the testosterone and testicular tissue of the mice in each group is observed in six weeks. Results：the content of blood testosterone，SOD and MDA of the exercising groups of the mice all changed，while T3 and T4 changed more significantly than T1 and T2，T1 and T3 changed more significantly than T2 and T4. Conclusion: the complement sea cucumber small molecule peptide can improve sports training， especially the aerobic exercise training which can let the level of the serum testosterone of the mice drop.