Intussusception is one of the common surgical emergency of infants and childhood in Korea. A clinical analysis was performed in 450 cases of intussusception in infancy and childhood, who were admitted to the Department of Surgery and Pediatrics, St. Marys Hospital from January 1973 to December 1988. The results were as follows; 1) The intussusception was commonly occurred under 1 year of age (84.7%), and male to female sex ratio was 2.2: 1. 2) There was no definitive seasonal variations in the incidence of intussusception, but slight increasing tendency of June and July. 3) The must important previous symptoms were URI (26.0%) and diarrhea (13.1%), but no definitive previous symptom was noted in 57.6%. 4) The present symptoms and signs were abdominal pain and irritability (92.9%), vomiting (82.9%), currant jelly like stool (76.4%) in that order. 5) The common anatomical types were ileocecal (44.1%) and ileocolic type (34.0%) 6) Overall recurrent rate was 8.2% : 7.5% in barium reduction cases and 0,7% in operative treatment cases. 7) Overall barium reduction success rate was 74.6% cases. And important prognostic factors were duration of symptoms, fever and leukocytosis. 8) Operative treatment was performed in 145 cases; manual reduction was made in 89.0% and intestinal resection was made in 11.0%. 9) The most serious complication of barium reduction was intestinal perforation (0.5%). 10) The surgical complication rate was 13.1%, and common post-operative complications were adhesive ileus (47.4%) and bronchiolitis (21.1%). 11) The operative mortality was 3.4%