To analyze the causes of failure to reduce acute infantile intussusception with gas enema. 441 cases of acute infantile intussusception in our hospital who failed to be reduced with gas-enema, and underwent the operative therapy were analyzed. Result: 92 cases (20.9%) were intestinal necrosis, 184 cases (41.7%) double intussusception, 27 cases (6.1%) organic pathological changes and 8 cases (1.8%) intestinal perforation caused by gas-enema reduction. All the cases had a successful recovery after surgery. Conclusion: The main causes of failure to reduction with gas-enema were as follows: ①double intussusception, ②intestinal necrosis, ③late for visiting a doctor, ④organic pathological changes, ⑤perforation (in the process of gas-enema reduction). The importance of early diagnosis is emphasized.