Objective To evaluate the feasibitity of robot-assisted posterior laparoscopic modified"single-position"radical nephroureterectomy.Methods A retrospective analysis was made on 7 patients receiving robot-assisted posterior laparoscopic single-position radical nephroureterectomy between April 2022 and April 2023.The patients were in a fully healthy lateral position,and an artificial pneumoperitoneum was established.Trocars were placed at the right costal margin of the posterior axillary line,3-4 cm above the iliac crest of the midaxillary line,6-8 cm below the anterior axillary line,and 3-4 cm above the iliac crest of the midaxillary line near the outer edge of the musculus rectus abdominis,respectively.After the kidney was removed,the ureter was freed down to the iliac vessels,and then the main joint of the robot was reversed 180° for redocking.The ureter was continuously freed downwards to the bladder wall and the catheter was clamped.The bladder was opened after filling with indocyanine green and distilled water mixture.Then the fluid in the bladder was washed,the contralateral ureteral orifice was observed,the affected side of the ureter was resected,and the bladder incision was sutured by two layers with V-LOCK 2-0 sutures.The incision was extended under the right costal margin of the posterior axillary line and 3-4 cm above the iliac crest of the midaxillary line to remove the specimen.Results The operation was successfully completed in all the 7 cases.The surgical operation time was 155-263 min(mean,247.0 min)and the blood loss was 20-100 ml(mean,42.9 ml).The postoperative anal exhaust time was 14-24 h(mean,22.6 h).There were 1 case of postoperative absorption fever,2 cases of moderate anemia,and 2 cases of postoperative incision fat liquefaction.In the 2 patients with moderate anemia,one patient developed postoperative intramuscular artery rupture leading to massive bleeding and the formation of hematoma in the surgical area,with the amount of bleeding being approximately 1000 ml,and the other had moderate anemia before and after surgery.The hospital stay ranged 8-16 d(mean,11.6 d).Pathologic examinations showed high-grade uroepithelial carcer in all the patients.Postoperative follow-ups lasted 3-9 months,with a mean of 6.2 months.None had bladder tumor recurrence or distant metastasis.Conclusion Robot-assisted posterior laparoscopic modified"single-position"radical nephroureterectomy is safe and feasible.