As a crucial component of clinical medicine, the main task of diagnosis is to cultivate students’ ability to master systematic clinical thinking, disease diagnosis process, comprehensive analysis methods, and the ability to solve clinical problems. Introducing case-based clinical reasoning as a novel and advanced teaching method in the diagnosis course, in line with the comprehensive ability teaching objectives of the course, can provide students with a platform to apply learned knowledge in practical cases, enhance the fun and practicality of learning, improve students’ clinical thinking ability and practical skills, enable students to make quick and accurate judgments when facing complex cases, and ultimately enhance their ability to analyze and solve problems comprehensively. This article combines the experience of applying case-based clinical reasoning to undergraduate diagnosis at West China School of Medicine of Sichuan University, and explores the prospects of applying this teaching method in medical diagnostics.