A 65-year-old man underwent radical cystectomy and cutaneous ureterostomy for bladder cancer. Because the patient had left complete duplex ureters, we modified the Toyoda method to construct the tubeless cutaneous ureterostomy with a unilateral stomal creation. The adhesive portion of both ureteral walls in duplex ureters was simultaneously cut approximately 5 mm from the distal end longitudinally, and the common sheath of the cut portion of the ureters was cut approximately 5 mm longitudinally in order to separate the two ureters. This procedure was repeated to make a“fish-mouth”aperture. Two opened ureteral walls were formed into the upper and lower plates of the Toyoda method stoma, respectively. To our knowledge, this is the first report of a surgical procedure of the tubeless cutaneous ureterostomy in complete duplex ureters.