A 4-week-old 0.5 kg male Shih Tzu with history of congenital abnormality, abnormality, was referred to Veterinary Teaching Hospital, Chungbuk National University for further evaluation and treatment. During physical examination, the dog revealed mild depression and dyschezia. In plain radiographs, a digital thermometer put in the anus and grasped blind end of the rectum. In contrast radiographs, a urethrorectal fistula was confirmed. Urine specimens were collected with cystocentesis. Bacteria of the urine were detected using an auto microorganism analyzer. According to history taking, physical examination, radiographic signs and urinalysis, it was diagnosed as type IV atresia ani with a urethrorectal fistula. The dog was treated by fistulectomy and anoplasty, and discharged with instruction. Three days after operation, mild dehiscence was appeared. Wound was left to heal by second intention. During the follow-up of eight weeks, wound showed it to be healed and defecation was normal.