Abstract： Objective To observe the effect of ultrasound-guided pectoral nerve block on perioperative analgesia and postoperative recovery of patients undergoing transaxillary endoscopic thyroidectomy,and to discuss its effectiveness and safety.Methods Sixty patients who received transaxillary endoscopic thyroidectomy in our hospital were selected and divided into 2 groups by random number table method,ultrasound-guided pectoral nerve block combined with general anesthesia group(Group P)and general anesthesia group(Group C),with 30 cases in each group.The patients in Group P were given with ultrasound-guided Pecs Ⅰ block combined with Pecs Ⅱ block for analgesia,and the patients in both groups were given with combined intravenous and inhalation anesthesia under tracheal intubation after induction.The peri-operative analgesic effect and postoperative recovery of the two groups were compared.Results In terms of perioperative analgesia,compared with Group C,the consumption of sufentanil during operation,the frequency of postoperative rescue analgesia and the consumption of ketorolac tromethamine during rescue analgesia were significantly reduced in Group P(P＜0.05).At 3,6,and 12 hours postoperatively,the NRS scores at rest and during movement were significantly lower in Group P(P＜0.05).Regarding postoperative recovery,Group P showed significantly shorter awakening time and PACU stay,and higher total QoR-40 scores at 24 hours postoperatively compared to Group C(P＜0.05).Specifically,in the dimensions of physical comfort and pain,Group P had significantly higher scores than Group C(P＜0.05).Conclusion Ultrasound-guided pectoral nerve block has a good analgesic effect in patients undergoing transaxillary en-doscopic thyroidectomy and is helpful for postoperative recovery.