Abstract: Objective To examine status of medical service seeking among runners of Shanghai International Marathon in 2013 and to explore risk factors of illness incident among participants of sport events.Methods Personal and clinical records of medical attendees participating Shanghai International Marathon in 2013 were collected from medical service station and analyzed.Results Records of 102 runners(81 males79.4%and 2120.6%females)seeking medical service were included in the analysis and 64.7%of the attendees were at the age of 20-40 years.Among the attendees,the proportion of the runners taking Mini Marathon or 10 km Run was higher than that of taking the whole course of the Marathon(P<0.01).A majority(46,45.1%)of the attendees sought medical service 3 hours after the beginning of the Marathon.The main reasons for seeking medical service were trauma,muscle spasms,and sprain.Conclusion Trauma,muscle spasms,and sprain are major aspects to be concerned in medical service and health education among marathon runners.