[Abstract] Objective To observe the efficacy and safety of transnasal humidified rapid insufflation ventilatory exchange(THRIVE) for the patients receiving hysteroscopy under intravenous anesthesia without endotracheal intubation. Methods One hundred and twenty patients of American Society of Anesthesiologists physical status I or Ⅱ, of Mallampatti I or Ⅱ, scheduled for hysteroscopy were divided into two groups (n=60 each) using a random number table method: the mask oxygen-inspiration group (group M) and the THRIVE group (group T). The group M maintained oxygen supply by face masks with sniffing position (100% oxygen, flow at 10L/min) and Group T via THRIVE (100% oxygen, flow at 30L/min and 70L/min after BIS<60). Cross-sectional area of the gastic antrum was stimated by ultrasound before and after THRIVE. Adverse reactions and treatments related to hypoxia during operation were recorded according to the procedure of SIVA. Other adverse events including involuntary limbs swing, choking cough, vomiting were recorded as well. Operation time, recovery time, total dose of propofol, adverse events including airway and air pressure injury related to THRIVE, satisfaction of the anesthesiologists, gynecologists and the patients were recorded after the operation. Results Compared with the group M, the incidence of SpO2<95%, jaw-lift, pressured mask and intraoperative involuntary limbs swing in the group T were significantly reduced(P<0.05), the dosage of propofol was increased (P<0.05), the satisfaction of anesthesiologists and gynecologists was significantly improved (P<0.05).The operation and recovery time had no significant difference (P>0.05). There was no significantly difference of cross-sectional area of the gastic antrum before and after THRIVE (P>0.05), no airway or air pressure injury occurred in the group T. Conclusion THRIVE can maintain oxygenation in patients under intravenous anesthesia without intubation during hysteroscopy more safely and effectively, reduce the incidence of the intraoperative involuntary limbs swing and improve the satisfaction of the anesthesiologists and gynecologists.