Objective To explore the effect of low-dose dexmedetomidine on hemodynamics of general anesthesia in hypertensive patients.Methods A total of 92 patients with hypertension were enrolled from May 2015 to February 2016 in People's Hospital of Fenghua District, Ningbo City were randomly divided into observation group and control group,with 46 cases in each group.All patients were treated with static and general anesthesia, the observation group before induction of general anesthesia 10 min received continuous intravenous micro-pump injection of dexmedetomidine 0.3 μg/kg(diluted with saline 20 mL);The control group received intravenous micro-pump injection physiology saline 20 mL.The mean arterial pressure(MAP)and heart rate(HR)before and after treatment, and the operation time, recovery time, extubation time, RSS sedation score and adverse reaction occurred were compared between the two groups.Results There was no significant difference in MAP and HR between the two groups before treatment.After treatment, the serum MAP of the two groups was increased, but the MAP in the observation group was(109.2±10.2)mmHg significantly lower than that in the control group(116.1±11.3)mm Hg,and HR in the observation group was(71.9±3.1)mmHg significantly lower than that in the control group(92.1±2.8)mmHg.The difference between the two groups was statistically significant(P<0.05).There was no statistically significant difference between the two groups in terms of operation time, recovery time and extubation time.The RSS sedation scores of the observation group before extubation(T1), extubation(T2)and extubation 1 min(T3)were higher than those of the control group.At T1, the RSS sedation score in the observation group was(2.3±0.4)points higher than that of the control group(1.8±0.3)points, At T2, the RSS sedation score was(2.9±0.4)points higher than that of the control group(2.1±0.3),At T3, the RSS sedation score was(2.5±0.3)points higher than that of the control group(1.9±0.3).The difference between the 2 groups was statistically significant(P<0.05).There was no significant difference between the two groups in adverse reactions.Conclusion Small doses of dexmedetomidine can reduce the patient's pumping, extubation and other stress response, providing the appropriate sedative effect, help to stabilize the patient's hemodynamic parameters, to ensure the effect of anesthesia and surgery to improve surgical safety.