Abstract: Objective　To understand the effects of long-time online learning of medical students and compare the effects of online and offline learning modes on medical students' professional knowledge acquisition and related abilities, thus proposing feasible countermeasures for the aspects that need attention in the later stages of medical students' school training and continuing education.Methods　A questionnaire survey was conducted with 420 medical students in their second year or above in Beijing, and key informant interviews were conducted with 3 teachers and 14 medical students. Statistical methods were used to describe the online learning effect and analyze the factors that may affect the learning effect.Results　Generally, long-time online learning led to the decrease of clinical theoretical knowledge mastery, clinical practice skills, communication skills, teamwork ability; yet, it also makes research investment time, innovation and entrepreneurship ability rise to a certain extent. Factors such as network lag, poor teacher-student communication and electronic product interference all had negative influence on learning effect.Conclusion　Long-time online learning has weakened students' knowledge mastery, and in the future, relevant knowledge should be supplemented in the design of clinical theory teaching and continuing education courses for different grades of medical students; online teaching exercises students' self-learning ability, and the online teaching experience should be fully summarized to comprehensively improve the comprehensive ability of medical students through the integration of online and offline teaching methods.

Key words: medical students, online learning, learning effect, medical education