The surgical management of anterior mediastinal masses are almost a consensus in great majority of cases. However, the surgical approach to reach optimal results, is in continuous debate. Therefore, we present a robotic strategy to achieve complete resection of a huge anterior mediastinal mass in a rare presentation of ectopic thyroids. We present a case of a 51-year-old female who sought medical care due to symptoms of breathless and a retrosternal compression sensation during decubitus. She had no signs of muscle weakness, eyelid ptosis or diplopia. The only medical record it was a left thyroidectomy past 10 years due to a benign nodule, with normal hormonal function without need of exogenous reposition. After a mediastinal enlargement on the x-ray, we proceeded to a CT-scan and an MRI that report an heterogeneous lesion with intervening cystic degeneration, intense contrast enhancement, measuring 5,6x4,6x6,3cm, and intimate contact with the brachiocephalic vein. A multidisciplinary board discussed the case and indicated upfront surgical resection. The patient was submitted to a Robotic Assisted Thoracoscopic Surgery (RATS) using a Da Vinci Xi® surgical platform (Intuitive Surgical, Inc. of Sunnyvale, CA) with three ports of 8mm for the robotic arms and one 15mm for the assistant on a left-side approach. The surgery begins by opening the mediastinal pleura just above the phrenic nerve in a counterclockwise dissection using a bipolar Maryland in the right hand. Due to the difficulty in identify the innominate vein, we proceed with an intravenous application of indocyanine green to use the Firefly™ function and properly localize the highlighted vein. After dissecting and isolating the innominate vein and control of internal mammary vein with hemoclip, we proceed the surgical dissection of the tumor by using the pericardium as posterior limit. Moving forward, the thymus was identified above de mass without any relationship with it suggesting that it was a tumor of non-thymic origin. The complete tumor resection with the adjacent thymus tissue undergone uneventful by the left robotic approach. The tumor was withdrawn from the chest cavity through a little enlargement (5 cm) of the accessory port without the need of rib retractor. The final anatomopathological result was ectopic thyroid tissue with no malignancy and adjacent thymic tissue with normal architecture for the age. The patient had a favorable evolution and was discharged on the 2nd post-operativ...