Abstract: This paper introduces the clinical experience of Professor GUO Yong in treating lung cancer- related fatigue based on syndrome differentiation. Professor Guo believes that, from the perspective of modern medicine, lung cancerrelated fatigue is closely related to disease stage, operation, chemoradiotherapy and targeted therapy, etc; from the perspective of Chinese medicine,deficiency of healthy qi and dual deficiency of the lung-spleen are the fundamental causes of lung cancer and lung cancer- related fatigue. Lung cancer- related fatigue mostly occurs in syndromes and types in lung cancer including dual deficiency of the lung-spleen syndrome,yin deficiency with internal heat syndrome and dual deficiency of qi and yin syndrome. In treatment, patients with dual deficiency of the lung- spleen syndrome shall take method of rectifying qi and fortifying the spleen as the therapeutical principle, as well as modified Sijunzi tang as the prescription; patients with yin deficiency with internal heat syndrome shall take method of nourishing yin and clearing heat as the therapeutical principle as well as modified Sanshen tang as the prescription; patients with dual deficiency of qi and yin syndrome shall take method of boosting qi and nourishing yin as the therapeutical principle as well as modified Shengmai yin as the prescription. In addition, the treatments for patients with phlegm or stasis should be modified according to their symptoms. It is suggested that the whole course of lung cancer treatment should pay attention to protecting the spleen and stomach as well as fortifying the spleen and supplementing the lung,so as to dispel pathogen and keep healthy qi.