Objective To investigate the effects of using dexmedetomidine instead of propofol on depth of anesthesia, wake-up test, anesthesia recovery and side effects during scoliosis surgery. Methods Sixty ASAⅠorⅡpatients aged 10-25 yrs weighing 25-64kg scheduled for posterior spinal fusion surgery were randomly divided into two groups with 30 patients in each group: dexmedetomidine (a loading dose of 1μg•kg-1 over 10 min followed by an infusion of 2.5 μg•kg-1•h-1) was administered in groupⅠwhile propofol was started at 100 μg•kg-1•min-1 in groupⅡ, and they are both adjusted to maintain a constant depth of anesthesia as measured by a BIS of 40～50. In both groups cisatracurium infusion was started at 1 μg•kg-1•min-1 and titrated to maintain TOF at 50%; remifentanil was infused at 0.4 μg•kg-1•min-1. MAP, CVP, HR, SpO2, PETCO2 and rectal temperature were continuously monitored during operation. Controlled hypotension was induced with nitroglycerin at 0.1～2 μg•kg-1•min-1 and MAP was maintained at 60-70mmHg. After dissection through muscles cisatracurium infusion was stopped. Wake-up test was began after spinal correction. Wake-up time and extubation time were recorded. Ramsay scores and Riker scores during wake-up test and anesthesia recovery were also recorded. The consumption of dexmedetomidine, incidence of intraoperative awareness, vomiting and shivering were investigated. Results The Riker scores during wake-up test and anesthesia recovery in Group Ⅰ was significantly lower than that of GroupⅡ（P <0.05）. There were no significant differences in Ramsay scores， incidence of vomiting and shivering between the two groups. No cases of intraoperative awareness was observed. Conclusion Instead of propofol, administering dexmedetomidine in conjunction with remifentanil and nitroglycerin in total intravenous anesthesia monitored by BIS during scoliosis surgery might provide sufficient sedative effect, raise the quality of wake-up test and anesthesia recovery, and has no effect on side effects.