Objective To investigate the efficacy and safety of different doses of dezocine at different administration time on analgesia after laparoscopic cholecystectomy.Methods 80 patients elected from ASA Ⅰ-Ⅱ grade laparoscopic cholecystectomy were randomly divided into four groups,20 cases in each group.Group Ⅰ was anesthetized by intravenously injected dezocine 0.10mg/kg before the surgery,group Ⅱ was anesthetized by dezocine 0.15mg/kg before the surgery,group Ⅲ was anesthetized by intravenously injected dezocine 0.10mg/kg after stopping anesthetic surgery,and group Ⅳ was anesthetized by intravenously injected dezocine 0.15mg/kg after stopping anesthetic surgery.The postoperative pain scores were observed 1,6,12,24 hours after operation in the four groups by using visual analog scale (VAS),comfort score (BCS),and anesthesia recovery score (modified Aldrete score).Results TheVAS of the four groups 1 hour after surgery:group Ⅰ and group Ⅲ was significantly different(t =2.308,P =0.036),group Ⅰ and group Ⅳ was significantly different (t =2.106,P =0.042),group Ⅱ and group Ⅲ was significantly different (t =2.711,P =0.014),group Ⅱ and group Ⅳ was significantly different (t =2.317,P =0.037).The BCS 1 hour after surgery:group Ⅰ and group Ⅲ was significantly different(t =2.108,P =0.042),group Ⅰ and group Ⅳ was significantly different(t =2.069,P =0.048),group Ⅱ and group Ⅲ was significantly different (t =2.353,P =0.033),group Ⅱ and group Ⅳ was significantly different (t =2.361,P =0.036).The VAS 6 hours after surgery:group Ⅰ and group Ⅲ was significantly different (t =2.084,P =0.045),group Ⅱ and group Ⅲ was significantly different(t =2.309,P =0.038),group Ⅱ and group Ⅳ was significantly different(t =2.303,P =0.040).The BCS 6 hours after surgery:group Ⅰ and group Ⅲ was significantly different (t =2.294,P =0.041),group Ⅱ and group Ⅲ was significantly different(t =2.322,P =0.035),group Ⅱ and group Ⅳ was significantly different (t =2.070,P =0.048).The BCS 12 hours after surgery:group Ⅱ and group Ⅲ was significantly different(t =2.518,P =0.047).VAS and BCS scores at other time points had no significant difference (P ＞ 0.05).Conclusion The analgesic after laparoscopic gallbladder surgery using dezocine 0.10mg/kg-0.15mg/kg,especially 0.15mg/kg administered anesthesia before surgery,can effectively relieve postoperative pain and improve postoperative comfort,reduce postoperative analgesic(pain pump) and has less adverse reactions,which is worthy of promotion.