[Abstract] Objective To investigate and compare the effects of postoperative analgesia that different doses of butorphanol advance injecting on laparoscopically hysterectomy. Methods 48 patients with general anesthesia undergoing laparoscopically hysterectomy, ASA I～II grade, were randomized into 4 groups(n=12):B1,B2,B3 groups received iv butorphanol 0.01,0.02,0.03mg/kg slowly in 10 minutes before skin incision, C group received saline as a comparison. Recording respectively the time of consciousness,VAS scores,Ramsay scores and adverse reactions after the end of surgery. Results The times of consciousness of B3 group were significantly longer than other three groups(P<0.05);The VAS scores of all experiment groups were lower than C group at each postoperation point (P<0.05),the VAS scores of B2 group and B3 group were lower than B1 group at each postoperation point (P<0.05); The Ramsay scores of all experiment groups were higher than C group after surgery,the Ramsay scores of B3 group were significantly higher compare to B1 group and B2 group at 2h,4h,6h after surgery.The incidence of dizziness of B3 group was higher than other three groups(P<0.05). Conclusion Advance intravenous injection butorphanol 0.02mg/kg have better postoperative analgesia effect and less adverse reaction,it is a suitable dosage use for gynaecological laparoscope. [Key words] butorphanol; advance intravenous injection; laparoscopically hysterectomy; postoperative analgesia;