Objective To investigate the use of laryngeal mask airway (LMA) ProSeal for airway management during open heart surgery performed under CPB in children. Methods Seventy-six ASA Ⅱ and NYHA class Ⅰ or Ⅱ patients aged 3 months-8 yr, weighing 3.3-34.5 kg undergoing open heart surgery under CPB were randomly divided into 2 groups ( n = 38 each): tracheal intubation group (group T) and ProSeal LMA group (group P1). Tracheal tube and LMA were inserted after induction of anesthesia with 8% sevoflurane. The rate of successfultracheal intubation and LMA placement, placement time, peak airway pressure and side effects during and after surgery including hypoxemia, tachycardia, bradycardia, hypotension and hypertension, laryngesl edema, dysphagia, bucking, dyspnea and hoarseness were recorded. Results There were no significant differences in the rate of successftl tracheal intubation and LMA placement, peak airway pressure, bucking, dyspnea and hoarse voice between the two groups (P＞ 0.05). The LMA placement time was significantly shorter than tracheal intubation time and the incidence of laryngeal edema and dysphagia lower in group P than in group T ( P ＜ 0.05). Conclusion The LMA ProSeal can provide adequate ventilation during operation with less complications and can be used effectively for cardiac surgery performed under CPB in children.