Over a 3 year period, 10 premature infants with less than 37 weeks of gestational age underwent ductal ligation for patent ductus arteriosus. No patient died during operations which were done at a mean age of 30 days. One late death at 2 months after operation was not directly attributed to operative procedure. Follow-ups were done in 9 survived patients from 2 to 26 months. Results suggest that surgical ligation is a feasible and effective method for treating symptomatic premature infants with patent ductus arteriosus.