Abstract: Objective: To analyze the relations between sub-health and physical exercise behavior in different gender medical students.Methods: Random sampling method was used to screen 338 medical students.The physical exercise behavior questionnaire included the length,frequency and intensity of exercises;the “SRHMS” scale included physical,psychological and social adaptation.Results: The boys' sub-health detection rate in physical,psychological,social adaptation and general health status were 43.4%,44.9%,41.2% and 41.2%,respectively,while the girls' were 54.5%,53.5%,48.5% and 52.0%,respectively.The difference was significant(P<0.05).Boys like long time,frequent and middle intensity exercises,while girls like medium time,medium frequent and middle intensity exercises.Students with low motion behavior had the highest sub-health detection rate,and students with moderate exercise behavior had the lowest detection rate.The difference was statistically significant(P<0.05).Conclusions: Sub-health is prevalent in medical college students.Girls have a higher sub-health rate than boys.Students with low exercise behavior are more prone to sub-health state.