Ｏｂｊｅｃｔｉｖｅ　To observe the effect of combination of dexmedetomidine and sufentanil on postoperative analgesia for patients undergoing laparoscopic hysterectomy.　Methods　Seventy-five（ASA Ⅰ-Ⅱ） patients undergoing laparoscopic hysterectomy were randomly allocated into three groups （n=25） after surgery： low-dose sufentanil group （group S1）， highose sufentanil group （group S2）， dexmedetomidine and sufentanil group （group DS）. All patients of the three groups received patients controlled intravenous analgesia（PCIA） after operation. The following setting： background， 1 ml/h （group S1： sufentanil 0.02 μg·kg-1·h-1, group S2： sufentanil 0.04 μg·kg-1·h-1, group DS： dexmedetomidine and sufentanil 0.02 μg·kg-1·h-1， each）. Bolus： 1 ml. Lock time： 8 min. The scores of visual analogue scales （VAS） and Ramsay at 1（T1），4（T2），8（T3），12（T4），24（T5），48（T6），72 h（T7） after aperation， effective presses/total presses of PCIA， the consumption of sufentanil during 72 h after operation， nausea and vomiting， pruritus， respiratory depression and the satisfaction degree of patients were recorded.　Results　Compared with group S2 from T1 to T4（VASr：2.98±0.77， 2.67±0.57， 2.33±0.65， 2.12±0.44. VASm：5.21±2.01， 4.32±1.13， 3.78±1.10， 3.12±0.86）， the scores of VAS（both at rest and movement， VASr and VASm） in group DS（VASr：2.03±0.64， 1.65±0.47， 1.62±0.49， 1.57±0.50. VASm：4.02±1.41， 2.61±0.93， 2.43±0.72， 2.44±0.74） significantly decreased （P<0.05）. Compared with group S1， the scores of VAS （both at rest and movement） significantly decreased in group S2 and DS at each time point（P<0.05）. While there were no significant difference in the scores of Ramsay， effective presses/total presses of PCIA and satisfaction degree of patients（P>0.05）. The consumption of sufentanil during 72 h after operation of group S1， S2， DS were respectively as follows：（208±36），（240±41），（165±38） μg， compared with group S1 and S2， the consumption of sufentanil significantly decreased in group DS （P<0.05）. The number of nausea and vomiting in group S1 were 10 （40%） and 4 （16%）， while nausea， vomiting and pruritus in group S2 were 12 （48%）， 4 （16%） and 3 （12%）. Only 5 patients （20%） in group DS had nausea， but no vomiting.　Conclusions　Combination of dexmedetomidine and sufentanil （0.02 μg·kg-1·h-1， each） was superior to simply application of sufentanil on the effect of postoperative analgesia for patients undergoing laparoscopic hysterectomy and complications decreased. This method can be safe and effective in clinical application.