【Objective】 To report the data of 4 cases of Trocar-assisted ureteroscopy in the treatment of transplanted renal ureteral stones, to analyze the effectiveness of this therapy, and provide a reference for the treatment of such patients. 【Methods】 Clinical data of 4 patients with ureteral stones of transplanted kidney treated at the Affiliated Hospital of Guizhou Medical University during Jan.2016 and Jul.2023 were retrospectively analyzed.All patients received auxiliary ureteral soft/rigid endoscopic combined with holmium laser lithotripsy after Trocar-assisted bladder fistula.Renal function was rechecked after surgery and all patients were followed up regularly. 【Results】 All 4 cases had upper ureteral stones.During the follow-up of 24-68 (average 38) months, no residual or recurrent stones were observed.Renal function and creatinine level returned to normal (79.0 μmol, 95.0 μmol, 60.6 μmol, 82.0 μmol, respectively). 【Conclusion】 The treatment of ureteral stones of transplanted kidney should be individualized.Bladder fistula with Trocar-assisted ureteroscopy can effectively protect the function of transplanted kidney, which is worthy of promotion and application.