Abstract: This paper presents a way on how to make large-scale online teaching design based on Tencent Classrooms after conducting an analysis of online teaching characteristics, and gives some dos and don’ts existing in the teaching processes and steps. The practice indicates that this teaching case can make use of the online teaching model to achieve the level of classroom teaching to a large extent, and obtain the corresponding teaching goals in the case of students without returning to school. Furthermore, this case study may provide some references on large-scale online teaching for other schools or departments.