Gene mutation in lung cancer refers to the mutation of a certain gene in the development of lung cancer that leads to the development of lung cancer, which is also known as driver gene. Currently, it is believed that the development of lung cancer is related to EGFR mutation, ALK mutation or Her2 overexpression, and there are already targeted drugs for EGFR, ALK and Her2 overexpression in clinical practice, and the use of targeted drugs is more effective than chemotherapy for lung cancer with head changes. Progression-free survival time or overall survival time is longer, therefore, lung cancer should try to have gene mutation test to find the target drugs that can be used before treatment. Once a targeted drug is available, it is not only more effective, but also better tolerated by patients.