OBJECTIVE： To investigate the effects of dexmedetomidine pretreatment on hepatic ischemia-reperfusion injury in patients with hepatocellular carcinoma radical surgery （HCRS）. METHODS： A total of 40 patients underwent elective HCRS were randomly divided into control group （20 cases） and observation group （20 cases）. Before operation， observation group was given Dexmedetomidine hydrochloride injection with loading dose of 0.7 μg/kg within 10 min， maintained at 0.4 μg/（kg·h） until the end of surgery. Control group was given constant volume of 0.9％ Sodium chloride injection as observation group and same anesthetic scheme. The levels of ALT， AST， IL-1， IL-6， CRP and TNF-α， the occurrence of ADR were observed in 2 groups before surgery， 4 h， 24 h， 72 h after surgery. RESULTS： Before surgery， there was no statistical significance in the levels of AST， ALT， IL-1， IL-6， CRP and TNF-α between 2 groups at different time points （P＞0.05）. After surgery， the levels of AST and ALT in 2 groups were significantly higher than before surgery， and the observation group was significantly lower than the control group， with statistical significance （P＜0.05）. The levels of AST and ALT in 2 groups were decreasing gradually as time. 4， 24， 72 h after surgery， the levels of IL-1 and IL-6 in 2 groups， TNF-α levels 4， 24 h after surgery and CRP levels 24， 72 h after surgery were significantly higher than before surgery， and the observation group was significantly lower than the control group； the levels of TNF-α in 2 groups 72 h after surgery were significantly lower than before surgery， with statistical significance （P＜0.05）. The levels of IL-1， IL-6 and TNF-α were decreasing gradually as time. There was no statistical significance in the incidence of ADR between 2 groups （P＞0.05）. CONCLUSIONS： Dexmedeptomidine pretreatment can relieve hepatic ischemia-reperfusion injury in HCRS patients， reduce the level of inflammatory cells without increasing the occurrence of ADR.