Abstract: The five-year survival rate of lung cancer, one of the cancers with higher morbidity and death rate, is less than 15%. Studies have shown that the occurrence of lung cancer is related to many factors in which epigenetics is an important one. In recent years, with the successful clinical application of epigenetic therapy drugs such as methylation transferase and histone deacetylase inhibitors that can enhance the sensitivity of chemotherapy, epigenetics has become a research hotspot. This paper briefly introduces the research progress in DNA methylation, acetylation, and cancer chemotherapy sensitivity in lung cancer diagnosis and treatment.