This article introduces Professor Liu Lingshuang’s experience in treating lung cancer in elderly by therapy of strengthening body resistance for treating cancer. It is considered that the etiology and pathogenesis are deficiency of vital qi,imbalance of yin and yang,decline of zang-fu viscera and invasion of pathogenic toxin. In clinical practice,the therapy of strengthening body resistance for treating cancer is taken as the principle,the treatment should balance yin and yang,invigorate spleen and tonify kidney and combine with accompanying symptoms. One prove case is presented.