Objective To present the preliminary clinical experience of robot assisted trans-subxiphoid (extended) thymectomy in patients with thymic neoplasms or myasthenia gravis. Methods A total of 62 patients (34 males and 28 females at an average age of 38±11 years) suffering from thymic neoplasms or myasthenia gravis who underwent robotic (extended) thymectomy via subxiphoid approach were included in our department between August 2016 and August 2017. All of the operation were completed through 4 ports. In details, the observation hole was created just below the xiphoid process, two ports for arm 1 and arm 2 were created below bilateral subcostal arch at the midclavicular line, and trocar for arm 3 was placed in the 5th or 6th intercostal space at the anterior axillary line, respectively. Patients with thymic neoplasms received thymectomy. Patients with myasthenia gravis received extended thymectomy. Results All the patients experienced uneventful operations. The mean operative time was 116.0±34.0 min. The mean intraoperative blood loss was 5.6±4.3 ml. The mean postoperative hospital stay was 4.0±2.2 days. There was no intra-operational massive hemorrhage, mortality, conversion or postoperative complication during the postoperative and follow-up period. Conclusion Robotic trans-subxiphoid thymectomy is safe and feasible, which is a promising technique for extensive application.