Abstract: Objective :To study the safety and effectiveness of the first-generation laryngeal maskairway (LMA) during general anesthesia of patients undergoing gastrointestinal cancer surgery. Meth-Ods :Forty-five patients (ASA,Ⅰ-Ⅲ) undergoing elective gastrointestinal cancer surgery were intubatedwith an indwelling gastrointestinal drainage catheter preoperatively. After the anesthetic induction, thefirst-generation LMA was inserted and a fibreoptic bronchoscope (FOB) was used to ensure correct po-sitioning of the LMA. The relationship of tidal volume, airway pressure and leakage of the LMA cuffduring mechanical ventilation was noted. The volume of fluid drained from the gastrointestinal tract andif the gas insufflated into the stomach were observed. Results :All the cases were evaluated as grade IIby the FOB. The glottis and the epiglottis could be seen for the placement of LMA. No air leakage wasobserved when the tidal volume maintained at 6 ml/Kg and the peak airway pressure was less than 20cm H2O. Airway leakage was observed in 77.8% (35/45) of the patients as the tidal volume increased to800 ml and higher or the peak pressure increased to 30 cm H2O. In all of the patients participating inthis study, no regurgitation or aspiration of gastric contents was found. The volume of drained fluid wasless than 30 ml. Conclusion :The correct contraposition of the LMA between the mouth and glottis inthe throat can decrease the peak pressure of the airway and can effectively prevent airway leakage. Thecontinuous negative pressure drainage of the gastric tube in the stomach can decrease the gaseous dis-tention of the stomach, circumvent the need for insertion of a decompression catheter into the stomach,and may prevent the regurgitation of gastric contents.