Objective To observe the application effects of postoperative analgesia of ultrasound guided transverses abdominis plane (TAP) block in patients undergoing hysterectomy.Methods 50 patients with hysterectomy under general anesthesia were selected,and they were randomly divided into two groups according to the digital table,25 cases in each group.The patients of group A were injected with 0.45% ropivacaine mesylate 20mL in ultrasound guided bilateral TAP after the end of surgery before extubation,the patients of group B were injected with the same amount of normal saline in ultrasound guided bilateral TAP block.Postoperative patient-controlled intravenous analgesia with sufentanil was provided to all patients.The VAS score of the two groups after operation,the postoperative dosage of sufentanil in 24h and pressing times of analgesia pump,and the satisfaction of patients with postoperative analgesia,and adverse reactions were observed.Results The VAS scores of 2h of group A (0.96±0.74)points vs.group B (1.88±0.73)points (t=4.45);The VAS scores of 4h of group A (1.52±0.65)points vs.group B (2.24±0.72)points (t=3.69);The VAS scores of 8h of group A (1.88±0.44)points vs.group B (2.68±0.56)points (t=5.64);The VAS scores of 12h of group A (2.24±0.52)points vs.group B (2.96±0.54)points (t=4.80);The VAS scores of 24h of group A (2.44±0.51)points vs.group B (3.24±0.44)points (t=5.99);there were statistically significant differences(all P=0.00).The postoperative dosage of sufentanil in 24h[group A (51.60±1.02)μg vs.group B (55.46±1.37)μg,t=11.30,P=0.00],the pressing times of analgesia pump[group A (7.20±2.04)times vs.group B (14.92±2.74)times,t=11.30,P=0.00],the satisfaction of patients with postoperative analgesia[group A (9.20±0.71)points vs.group B (7.52±0.77)points],t=8.03,P=0.00].There were 2 cases of postoperative nausea and vomiting in group B,and 8 cases in group A,the difference was statistically significant(x2=4.50,P=0.03).Conclusion The application of postoperative analgesia of ultrasound guided TAP block in patients undergoing hysterectomy can reduce postoperative intravenous analgesic drug usage,reduce the incidence of adverse reactions induced by drugs,improve patients' comfort and satisfaction,it is suitable for clinical application.