As the first treatment of choice for medically inoperable patients with early stage non-small cell lung cancer,it is demonstrated that the therapeutic outcome of stereotactic body radiation therapy (SBRT)is similar to that of surgery,but the data is mainly from nonrandomized controls and retrospective studies.More cases of randomized prospective clinical trials are needed to confirm the conclusions.The biologically effective dose ＞ 100 Gy is associated with improved local control and overall survival,and the small tumor volume is correlated with higher local control rate.