Objective To evaluate the effects of intensive insulin therapy (IIT) versus conventional insulin therapy (CIT) in treating of severe traumatic brain injury (sTBI).Methods Systematic searching of randomized controlled trials (RCTs) in literature databases were performed for meta - analysis by Review Manager.Outcome parameters were the early (in hospital ) and the late (3 months later) mortalities,infection rates,good late neurological severity scale (NSS) score frequency,and hypoglycemic episodes.Results Twelve studies and 1 277 patients were included in this meta - analysis.The pooled OR of early mortality was 0.78 (95% CI:O.53 - 1.15,P =0.21 ).The pooled OR of late mortality was 0.85 (95% CI:0.63 -1.15,P =0.30).The pooled OR of infection rate was 0.49 (95% CI:0.37 -0.64,P <0.00001).Meanwhile,The pooled OR of late good NSS frequency was 1.62 (95% CI:1.18 -2.21,P =0.003).Furthermore,The pooled ORs of hypoglycemic episode frequency were 4.33 (95% CI:1.39 - 13.49,P=0.01) and2.61 (95% CI:2.27-2.99,P<0.00001).Conclusions In treating of sTBI,IIT had no obvious beneficial effect on early and late mortality compared with CIT.However IIT could decrease infection rate,improve late NSS score.Meanwhile,hypoglycemic episode frequency was significant higher in IIT group other than CIT group.It is still need further study to clarify whether IIT should be continued in treatment of sTBI. Key words: Brain injury; Insulin; Meta-analysis