Owing to the prevalence of robot-assisted thoracoscopic surgery and the increase in the number of small lung cancer cases, robot-assisted thoracoscopic segmentectomy cases have also been increasing. For small lung cancers, such as ground-glass opacity lesions, identifying the location and securing a sufficient free margin from the main tumor can be difficult. We have already developed and reported the clinical application of a new marking system, a radiofrequency identification marker. In the current study, we applied this technique to robot-assisted thoracoscopic segmentectomies. Concomitant with other devices, we believe that robot-assisted thoracoscopic surgery has a great advantage in segmentectomy.