Lobectomy is the standard surgical procedure of non-small cell lung cancer (NSCLC). Based on parenchymal-sparing advantage, better postoperative lung function, rapid recovery and less invasiveness, segmentectomy has been widely used in early peripheral non-small cell carcinoma in recent years. But there was no randomized clinical trials confirming survival benefit of segmentectomy. Led by Asamura, the Japanese Clinical Oncology Group (JCOG) has conducted a series of studies on this topic. Ever since the presentation at the 101st Annual Meeting of the American Society of Thoracic Surgeons (AATS) in 2021, the results of JCOG0802/WJOG4607l have triggered massive debate. This study was aimed at determining whether segmentectomy was non-inferior to lobectomy in overall survival in patients with early peripheral NSCLC (tumor diameter≤2 cm and consolidation tumor ratio>0.5), and the results were published in The Lancet on 22 April 2022. The 5-year overall survival rate was higher in the segmentectomy group than that in the lobectomy group, despite a higher rate of local recurrence, suggesting that segmentectomy should be the standard surgical procedure for those patients. Results of this study provide high-level evidence-based medicine evidence for the safety and effectiveness of segmentectomy, and are expected to promote the application of segmentectomy in those patients or even more other patient populations. However, due to the increased local recurrence rate and unsatisfactory postoperative lung function, there are still problems to be solved to make segmentectomy a standard surgical procedure. This paper interprets this study, discusses its instructiveness in clinical practice and summarizes its limitations.