These studies were performed to establish more effective surgical method for correcting congenital atresia coli in calves. Distal colon fistulation, proximal colon fistulation and colon anastomosis which could be applied for surgical repair of intestinal obstruction were carried out in goatlings experimentally and in calves with atresia coli clinically. After treatment of the animals clinical signs, blood component values, body weight gain, survival and necropsy findings were observed. In goatlings, clinical signs after colon fistulation were diarrhea, anorexia and vitality loss, and those of proximal colon fistulation group were severer than those of distal colon fistulation group. Surviviability after operation was 9~16 weeks in distal colon fistulation group, 2~8 weeks in proximal colon fistulation group, and 2-3 days in colocolic anastomosis group, respectively. There were no alterations in blood component values among experimental groups. Weight gain rates were 54.6% in distal colon fistulation group and 42.9% in proximal colon fistulation group compared with those of control. Necropsy findings observed in experimental groups were distension of intestine and excessive fluid in abomasum and intestine. Two calves with atresia coli died 1 day and 6 days after operation but one with colon fistulation survived more than two months. Preoperative clinical signs in calves with atresia coli were abdominal distension, progressive anorexia, no defecation and postoperative clinical signs wert diarrhea and periodic abdominal distension. After operation there were no alterations in blood component values between the calf with atresia coli and control calf. Weight gain rate of calf with atresia coli was similar to that of control but revealed the tendency to decrease from the 2nd month after operation. Necropsy findings observed in two calves with atresia coli were intestinal distension. intraluminal excessive fluid, blind atretic sac and absence of intrarectal content. It was concluded that proximal or distal colon fistulation could be available for surgical correction of congenital atresla coli and prognosis of distal colon fistulation was better than of proximal colon fistulation, but that extensive colocolic anastomosis could not be compatible with life in ruminants.