Ｏｂｊｅｃｔｉｖｅ　To evaluate the efficacy and safety of supraglottic jet ventilation and modified laryngeal mask airway during painless fiberbronchoscopy.　Methods　Eighty patients undergoing painless fiberbronchoscopy were randomly divided into 2 groups(n=40), receiving supraglottic jet ventilation (J group) and modified laryngeal mask airway (L group), respectively. The outcomes of the procedures were recorded, including success rate of the first tubing insertion, the time spent in successful positioning of the tube, the stability of the tube, and related complications. Furthermore, MAP, HR, SpO2 and PETCO2 were monitored before anesthesia(T0), immediately after inserting laryngeal mask airway(or nasopharyngeal ventilation)(T1) or fiberbronchoscope through the glottis(T2), and 3 min(T3) after and by the end of fiberbronchoscopy.　Results　The success rate of the first tubing insertion and exposure condition in J group(100%, 97.5%) are better than L group(81.1%, 81.1%)(P＜0.05). The time spent successfully positioning the insertion and time of check in J group [(10.8±2.6) s, (12.9±4.4) min] are shorter than L group [(23.2±12.7) s, (23.2±9.5) min] (P＜0.05). The satisfaction degree of patients in J group is better than that in L group (P＜0.05), and there are no significant difference of the satisfaction degree of doctors in two groups (P＞0.05). The occurrence of sore throat in J group(81.1%) is less frequent than that in L group(12.5%)(P＜0.05). Other complications are not significantly different in two groups(P＞0.05).　Conclusions　Supraglottic jet ventilation for painless fiberbronchoscopy is a safer and more effective procedure than modified laryngeal mask airway.