Robot-assisted thoracoscopic surgery( RATS) and video-assisted thoracoscopic surgery are minimally invasive surgical approaches to the chest wall that avoid sternotomy. We report on the innovations in RATS mediastinal tumor surgery performed in our department. We use a lateral approach, and the robotic arm is inserted between the third, fifth, and seventh intercostals and below the costal ribs. Carbon dioxide gas is insufflated using a pneumoclear insufflator. A small thoracotomy is made in the fifth intercostal space and an Alnote Lapsingle is placed and a scope and assistant port are implanted. The Alnote Lapsingle is used to keep the chest wall airtight and stable. The scope is moved less, reducing interference with the assistant. Tissue can now be placed in the retrieval bag with a good surgical field of view. After much trial and error, RATS mediastinal tumor surgery can now be performed more easily.