Objective: The paper investigates the college students' participation in medical insurance, with college students from Lanzhou University as the main subjects. Methods: A self-filled questionnaire survey was used to investigate the medical insurance participation and willingness of college students. Results: 3902 questionnaires were collected, and 3602 were valid with an effective rate of 92.31%. 54.86% of college students participated in medical insurance at school, 41.95% of college students participated in medical insurance in registered residence, but not at school. Only 3.19% of college students neither participated in medical insurance at school nor registered residence. Top reason for not being insured at school is that most students think it is more convenient to participate in the registered residence. Other reasons include students' intention, cognition of medical insurance, family economic conditions, purchase of commercial health insurance and inadequate publicity of policies in their schools and so on. Conclusion: It is suggested that college students should be included in the basic medical insurance system for urban and rural residents and must be insured at school. We should strengthen the publicity of medical insurance participation, improve students' cognition of medical insurance policies, coverage and other basic contents, so that effectively expand medical insurance coverage.