Abstract：There are abundant records about the lung heat in ancient books of Chinese medicine，but at present，there is no detailed discussion or clear definition in textbooks and reference books of Chinese medicine. Although there were many explanations about the etiology and pathogenesis of the lung heat in the past，the related discussions were scattered. The authors tried to conduct an in-depth study on the etiology and pathogenesis of the lung heat in ancient books and literature of Chinese medicine，as well as discuss and analyze different academic opinions of pathologenesis of the lung heat proposed by ancient scholars. It is believed that the understanding of the pathogenesis of the lung heat in ancient books of Chinese medicine includes exterior pathogen invading the lung，excessive lung qi，the heart fire affecting the lung，blood heat and stagnation，fire heat restraining metal and hidden pathogen. These findings are conductive to exploring the clinical thinking of Chinese medicine，enhancing the treatment level of Chinese medicine，and providing basis for the clinical scientific research of Chinese medicine.