Abstract: Lung cancer is one of the most common cancers with the highest incidence and mortality. At present, imaging and pathological biopsy are mainly used for early screening and diagnosis in clinical practice. Circular RNA (circRNA) is stably present in lung cancer tissues and body fluids of patients, and is a promising biomarker for cancer diagnosis and prognosis evaluation. In this paper, the role and value of circRNA in the diagnosisand prognosis evaluation of lung cancer were reviewed from the perspectives of lung cancer tissue and body fluid, and the problems existing in current clinical studies were also discussed.