Abstract: Objective: To investigate the effects of the different doses of dexmedetomidine on the adverse reactions in the patients treated with resection of hepatocellular carcinoma during recovery period.Methods: Sixty patients scheduled by resection of hepatocellular carcinoma were randomly divided into the dexmedetomidine 1 and 2 group(D1 and D2 group) and control group.D1 and D2 group were treated with 0.5μg/kg and 1μg/kg of dexmedetomidine by continuously intravenous injection for 10 min before 30 min of the end of operation,respectively,and the control group were treated with the same volume 0.9% sodium chloride injection.The blood circulation,awakening and extubation time,and restlessness and sedation score in 3 groups during recovery period were observed.Results: The blood pressure and heart rate at each time-point during peri-extubation and postoperative restlessness score in D1 and D2 groups were significantly lower than those in control group(P<0.01),while the sedation score in D1 and D2 groups was significantly higher than that in control group(P<0.01).The differences of the awakening time and extubation time between D1 group and control group were not statistically significant(P>0.05),while the awakening time in D2 group was significantly longer than that in control and D1 groups(P<0.01).Conclusions: The intravenous injection with 0.5μg/kg of dexmedetomidine at 30 min before the end of operation can keep the stabilization of hemodynamics during recovery period,reduce the restlessness,and does not affect the awakening time in the patients with resection of hepatocellular carcinoma.