Abstract: The paper summarizes the theoretical basis of the Compound Method Theory proposed by the first TCM master Professor Zhou Zhongying for the treatment of exogenous febrile diseases. The theoretical basis is the rapid development of the disease and its continuity; pathological factors are intertwined and mutually causal; the disease is retained and transmitted, and multiple organs are related; the condition is critical and dangerous, with a mix of ups and downs. The key points of applying the complex method are to identify pathological factors and distinguish between the primary and secondary factors; identify the location of the disease and pay attention to the relationship between pathogenic factors and positive factors; clarify the excess and deficiency of cold and heat, in order to achieve a peaceful balance between yin and yang; predict the spread of the disease and promptly intercept and reverse it. The commonly used compound methods for external febrile diseases, such as clearing qi fen and cooling ying fen, resolving the exterior and interior, and promoting the upper, dispersing the middle, and guiding the lower were proposed. The treatment of severe external febrile diseases such as syncope and prolapse was also carried out using the methods of promoting qi and blood circulation, strengthening healthy qi and consolidating the body.