Objective:To systematically evaluate the association of human epidermal growth factor receptor-2（Her-2）with the prognosis of non-small cell lung cancer（NSCLC）.Methods:Related databases including Cochrane Library

EMbase

PubMed

and CNKI were searched for the studies on Her-2 and the prognosis of NSCLC.Newcastle-Ottawa Scale（NOS）was used to assess the risk of bias

and Revman5.3 and Stata15.1 software were used for statistical analysis.Results:A total of 20 historical cohort studies were included

with an NOS score of

>

6

and there were 6199 cases in total.The studies included had relatively low heterogeneity（I

2

= 33%）

and the pooled analysis with the fixed effects model showed a hazard ratio of 2.14（95% confidence interval:1.85 ～ 2.47

P

<

0.000 01）

suggesting that Her-2 overexpression was associated with the poor prognosis of NSCLC patients.The subgroup analysis showed that Her-2 overexpression was associated with the prognosis of NSCLC in patients with different stages or tissue types.The Begg rank correlation test showed no obvious publication bias.Conclusion:Her-2 overexpression is associated with the poor prognosis of NSCLC

which is indicated in different stages and tissue types.Since the articles included are mainly historical cohort studies

more prospective cohort studies are needed for further validation.