ObjectiveTo investigate the clinical manifestations, diagnosis and treatment of diaphrammatic paralysis (DP) in infants with congenital heart disease (CHD) after cardiac surgery. MethodsBetween October 2008 and June 2014, among 2 962 infant patients ( < 1 year) underwent cardiac surgery for congenital heart disease, postoperative DP was diagnosed in 31 patients. The paralysed hemidiaphragm was left side in 10 patients, right side in 15 patients, and bilateral in 6 patients. There were 22 males and 9 females. The age at operation was 1-12 (4.5±4.2) months on the average. The body weight at operation was 2.9 to 8.5 (5.6±2.2) kg on the average.All children received mechanical ventilation. ResultsNo patient died in this study.There was a statistical difference between preoperative and postoperative mechanical ventilation time at 123-832 (420±223) hours versus 15-212 (75±58) hours (P < 0.05). ConclusionsDP caused by phrenic nerve injury during surgical intervention for congenital heart disease is an important risk factor in terms of morbidity during the postoperative period. Diaphragmatic plication appears a good option, especially in infant children, to wean patients from mechanical ventilation and to prevent long-term side effects of mechanical ventilation.