The diagnostic methods and pathogenesis theory of traditional Chinese medicine are one of the core contents of traditional Chinese medicine. Through the comprehensive application of the four diagnostic methods, pulse diagnosis, tongue diagnosis, etc., doctors can obtain more comprehensive and accurate diagnostic information, thus formulating more scientific and personalized treatment plans. The theory of etiology and pathogenesis provides doctors with a basic theory for treating diseases, enabling them to better understand the essence and development laws of diseases, and formulate corresponding treatment plans. Although the diagnostic methods and pathogenesis theories of traditional Chinese medicine play an important role in clinical practice, they still need to be better adapted to the needs of modern medicine through long-term practice and continuous improvement. This review aims to explore the diagnostic methods and pathogenesis theories of traditional Chinese medicine, provide reference and reference for the development of traditional Chinese medicine, and contribute to the promotion of traditional Chinese medicine and the inheritance of Chinese culture. Keywords Diagnostic method; Causationism; Five elements and six weathers; Future development Traditional Chinese medicine, as a treasure of traditional medicine, has a long history and profound traditional background. It has a long history and can be traced back to ancient times. After thousands of years of development and evolution, it has formed a unique theoretical system and treatment methods. Traditional Chinese medicine, with its unique inspection methods and dialectical treatment theory, has provided valuable experience and wisdom for the health of the Chinese people for thousands of years.The diagnostic methods of traditional Chinese medicine are mainly based on the four diagnostic methods, namely inspection, listening and smelling examination, inquiry, palpation. The four diagnostic methods are the foundation of traditional Chinese medicine diagnosis. By observing the patient's external manifestations and internal changes, combined with information such as medical history, symptoms, and signs, the nature and severity of the disease can be determined. The theory of etiology and pathogenesis in traditional Chinese medicine emphasizes the fundamental causes and pathogenesis of diseases, believing that the occurrence and development of diseases are a combination of multiple factors, such as changes in the internal and external environment of the human body, emotional factors, and improper diet. With the rapid development and technological progress of modern medicine, the position and value of traditional Chinese medicine in the field of modern medicine are increasingly valued.