Lung cancer is a prevalent malignant tumor and the leading cause of cancer-related death globally. Frailty is a serious problem in an aging population and has received widespread attention in the development of oncology. Frailty is a clinical syndrome of physiological reserve decline, resulting in increased physical vulnerability and diminished anti-stress ability. Moreover, it is closely related to complications and mortality in treatment, and affects the prognosis of lung cancer patients. In this article, we reviewed the assessment tools, mechanisms, adverse effects on prognosis, and interventions for frailty in lung cancer, aiming to better understand frailty and help identify and manage frailty in lung cancer patients.