Due to the ongoing public health crisis, computer online teaching has become a new normal. It is very meaningful to explore how to effectively apply computer in online teaching. In this paper, the online teaching situation of teachers and students in a college was surveyed and analyzed. Then, DingTalk, the most popular online teaching platform among the respondents, was introduced in details. Next, the online teaching situation was tracked, and the learning situation was evaluated in terms of pre-class preparation, in-class teaching, and after-class homework. After that, the satisfaction with the course design and teaching effect was surveyed. The results show that the students felt satisfied with the course design, but regarded practical teaching a weak link in online teaching; the students highly recognized the work attitude, teaching ability, and interactive ability of their teachers, yet calling for better innovation awareness among teachers. The research results provide a good reference for computer-based online teaching of professional courses.