Since January 2020, due to the epidemic of coronavirus disease 2019, all universities in China have postponed their studies or even suspend their studies. In response to the teaching policy of “suspending class, but keeping teaching and learning” , college teachers have rapidly changed into online teaching mode. However, how to ensure the quality and effect of online teaching still needs further exploration. Through analyzing the course characteristics of medical imaging diagnostics and students’ learning situations, this study discusses how to design detailed online teaching projects and improve the teaching quality and how to select online software suitable for the course. A questionnaire survey was conducted to evaluate the effect of online teaching during the spring course in 2020, selecting a total of 297 clinical and other undergraduate students of grade 2017 from West China School of Medicine of Sichuan University. The results showed that the detailed online teaching programs including “video learning” “distance teaching” “periodic examination” “weakness tutorial” were helpful to the learning process agreed by the majority of students. During the epidemic period, online teaching method can help students master the content of medical imaging diagnosis. In the era of Internet, the “online+offline” teaching mode is expected to be popularized in the future.