Objective: To evaluate the benefits and risks of tight glycemia control （TGC） versus conventional glucose control （CGC） in critically ill brain-injured adults. Methods: We performed meta-analysis by systematically searching PubMed

EMBASE

OVID

ScienceDirect

Web of Science

CNKI

Wanfang Data

and CQVIP databases to retrieve RCTs in any languages. We used Review Manager to perform meta-analysis. Odds ratios （ORs） or weighted mean differences （WMDs） with 95% confidence intervals （CIs） were calculated in analyses. Results: Twenty-six RCTs with a total of 3

759 participants were included in this meta-analysis. In-hospital mortality showed significant dissimilarity between TGC and CGC groups with OR of 0.76 （95%CI 0.58

0.99）. However

in terms of overall mortality and long-term neurological severity outcome

it didn’t show differences with ORs of 0.93 （95%CI 0.79

1.10） and 1.15 （95%CI 0.96

1.37）. There were also discrepancies in infection rate and ICU length of stay with OR of 0.51 （95%CI 0.42

0.62） and WMD of -2.37 （95%CI -2.99

-1.74）. Significances were observed in hypoglycemia events with ORs of 6.24 （95%CI 4.83

8.07） and 2.73 （95%CI 2.56

2.91） using two methods. Conclusion: In critically ill brain injury

TGC did not show beneficial effects on reducing overall mortality and long term neurological outcome

but it increased the risk of hypoglycemia.