Lung cancer is currently the most common malignant tumor in the world. It ranks first among male and female malignant tumor deaths and poses a serious threat to human health. Chronic obstructive pulmonary disease (COPD) is the most common chronic inflammatory disease of the respiratory system. Patients with lung cancer and COPD are also commonly seen in clinical work. In epidemiological studies, lung cancer and chronic obstructive pulmonary disease There is often a certain relationship between the two, with a higher incidence and mortality, which will cause greater harm to the patient's health. By analyzing the pathogenesis of the two diseases in the past, the causative factors are the same, which is explained in detail in this article.