A 65-year-old man underwent a radical retropubic prostatectomy for prostate cancer, and 5 days later fecaluria and serous diarrhea appeared suddenly. Cystourethrography domonstrated the flow of contrast material into the rectum through the fistula, so we diagnosed a rectourethral fistula. We first attempted conservative management, but the fistula did not close spontaneously. So we performed the transanal repair of rectourethral fistula about 2 months after surgery. This repair was effective, and the patient was alive without fistula recurrence at about 2 years after the repair surgery. This approach is simple and does not require a new incision, but it is only useful for low rectourethral