Abstract: Objective To examine the prevalence and the impact factors of sub-health among military medical college students and to provide comprehensive evidence for sub-health intervention.Methods Stratified cluster sampling method was adopted.Totally 1 295 undergraduates from three military universities in Chongqing city were selected for a questionnaire survey.Results The overall prevalcence rate of sub-health was 66.41%.The rate of physical sub-health was 19.15% and that of psychological was 58.22%.Females(82.61%) had a higher prevalence rate of sub-health(χ²=5.611,P=0.018) compared to the males.There were statistical significances in the rates among the studetns of different colleges and grades(P< 0.01).The risk factors of sub-health were being afraid of hot weather,without regular time table,dissatisfaction with the life,without successful academic record,unable to cope with daily life,the lack of sleep,hard to concentrate one's attention,preference for sweet foods,study pressure,and dissatisfaction with their family condition.Conclusion The sub-health status is serious among military students in Chongqing city.More attention should be paid to the health of the students and some intervention measures should be taken.