INTRODUCTION: To describe our technique for robot-assisted radical nephrectomy (RARN) with inferior vena cava (IVC) tumor thrombectomy and to present initial results for our first two patients. MATERIALS AND METHODS: Two patients with renal masses with infrahepatic IVC extension underwent RARN with IVC tumor thrombectomy using a four-arm configuration. Both cases were right-sided tumors. Vascular control was obtained with complete cross-clamping of the vena cava with robotic bulldog clamps. Intraoperative ultrasound was used to delineate extent of tumor extension. Specimens were removed en-bloc, and the IVC was closed with 2-layers of 4-0 Prolene. The specimen is extracted through a lower midline incision. RESULTS: Two robotic IVC thrombectomies were successfully completed. There were no conversions, intraoperative or postoperative complications. Median operative time was 243 minutes with a median estimated blood loss of 150 mL. Both patients were able to ambulate independently free of intravenous opioids on postoperate day 1. Median length of stay was 4.5 (range 3-6) days. Final pathology revealed clear cell RCC in both cases with negative surgical margins. CONCLUSIONS: Robotic technology may facilitate RN and IVC thrombectomy in the well selected patient and appears to be a safe and feasible approach.