Objective To investigate the preemptive analgesia therapy of dezocine on postoperative agitation in patients undergoing Esophagectomy under thoracoscopy.Methods Sixty cases of ASA Ⅰ,Ⅱ undergoing thoracoscopic resection of esophageal cancer patients were divided into two groups randomly:dezocine and control group,each group with 30 patients.Patients in dezocine group were intravenously injected with dezocine 0.1 mg/kg before intubation,and patients in control group just intubation as usual.The incidence of postoperative agitation in two groups were observed,and visual analog scale(VAS) score at 0 min,15 min,30 min and 45 min after extubation were registered.The time of wake up and extubatio,the change of hemodynamic were also recorded.Results The incidences of postoperative agitation in dezocine preemptive analgesia group were obviously lower than that in the control group (10％ (3/30) vs.60％ (19/30),P ＜0.01).The VAS score at 0 min,15 min,30 min and 45 min after extubation in dezocine preemptive analgesia group ((1.3 ± 1.2),(2.4 ± 1.7),(2.7 ± 1.3),(2.8 ± 1.2) points) were significantly lower than those in the control group ((3.4±1.5),(4.7±1.8),(5.0±1.6),(4.8±1.7) points) (F within group =18.6,P＜0.05; F between group =20.4,P ＜ 0.05 ; F interaction =20.0,P ＜ 0.05 ; compared different time between two groups,all P ＜ 0.01).Conclusion Preemptive analgesia with dezocine can obviously lessen postoperative agitation in patients undergoing Esophagectomy under thoracoscopy,and dezocine is also effective in postoperative analgesia.