Lung cancer is the leading cause of mortality. As life expectancy is prolonged, morbidity of lung cancer is increased. As of 2023, various mechanisms of molecularly-targeted drugs are available in the market. Guideline is reviewed and revised every few years based on the latest reliable evidence. Treatment of lung cancer depends on the subtype and stage of lung cancer based on TNM classification. Choice of molecularly-targeted drug depends on the types of specific genetic mutation and performance status of the patient.