A 21-year-old woman who had been injured in a traffic accident appeared with abdominal pain and macroscopic hematuria. Computed tomography (CT) performed 6 hours after the injury showed extravasation of contrast medium in the right retroperitoneal space. Retrograde pyelography (RP) showed the interruption of right ureter at the site of ureteropelvic junction. We performed an abdominal operation 15 hours after the injury under the diagnosis of right ureteral avulsion. We observed a completely separated right ureter at the ureteropelvic junction, and performed an end to end anastomosis. The patient was discharged three weeks after surgery, and has not had any problems for three years.