目的 了解医学生长时间线上学习效果，比较线上与线下学习模式对医学生知识掌握程度与能力培养的影响，为后期医学生在校培养与继续教育提出建议。 方法 采取线上线下相结合的方式，对北京市397名大学二年级以上的医学生开展问卷调查，对3名教师和14名医学生开展关键知情人访谈；采用描述性统计、秩和检验和多元线性回归分析模型描述在线学习效果并分析其影响因素。 结果 长时间线上学习使得医学生创新创业能力在一定程度上有所提升，但也导致医学生临床理论知识掌握程度、临床实践技能、沟通表达能力、团队协作能力有所下降；网络卡顿、师生交流不畅、电子产品干扰等因素均对学习效果有负面影响。 结论 长时间线上学习削弱了学生知识掌握程度，未来对不同年级医学生，在临床理论教学与继续教育课程设计上应对相关知识予以补充；线上学习锻炼了学生自主学习能力，应充分总结线上教学经验，通过线上线下融合教学方式，全面提升医学生综合能力。

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.