The academic research of traditional Chinese medicine （TCM） classical formulas has not yet established its own unique theoretical and methodological system， and the methods for studying classical formulas must align with the principles and laws of TCM. Using the

Xiaochaihu Decoction

（小柴胡汤） related formulas in

Treatise on Febrile Disease

（《伤寒论》） as a starting point， this paper explores a research metho

d system for classical formulas based on the organic combination of interpretation， comparison， and inductive-deductive methods. It integrates both TCM and western medical theories to elucidate the connotations of classical formulas， analyze and summarize their mechanisms and patterns， and extend their application to the treatment of modern diseases. It is proposed that a scientifically systematic approach to TCM research will facilitate the derivation of higher-level academic principles， thus refining the research methodology for classical formulas. This can serve as an important component of the inheritance and innovative foundation for the development of TCM.