Abstract: Objective To explore the relationship between microsomal epoxide hydrolase（EPHX1）polymorphism and genetic sus-ceptibility to hepatocellular carcinoma（HCC）. Methods Both English- and Chinese-language databases were searched for relevant lit-erature on the relationship between EPHX1 polymorphism and HCC using a preformulated search strategy.Data on the association were evaluated using odds ratio（ORs）with 95% confidence intervals（CIs）， and heterogeneity of included studies was assessed. Meta-analysis of published data was carried out using Stata 12.0 software. Results Nine studies were included based on the selection crite-ria 8 studies，involving 584 cases and 989 controls，examined the EPHX1 polymorphism 337T>C.Significant increased risk of HCC was found using the additive model［C vs T OR（95%CI）=1.47（1.26~1.72），P<0.001］，homozygote comparison［CC vs TT OR（95%CI） =1.88（1.40~2.52），P<0.001］，and the recessive model［CC vs CT/TT OR（95%CI）=1.73（1.36~2.21），P<0.001］.A total of 6 studies in-volving 432 cases and 699 controls examined the EPHX1 polymorphism 416A>G.Markedly decreased risk of HCC was observed using the additive model［G vs A OR（95%CI）=0.75（0.59~0.95），P=0.018］. Conclusions The EPHX1 polymorphism 337T>C is associated with HCC，and the CC genotype appears to be a risk factor.In contrast，the G allele of the EPHX1 polymorphism 416A>G may de-crease HCC susceptibility and therefore constitute a protective factor against HCC.

Key words: Hepatocellular neoplasms, Microsomal epoxide hydrolase, EPHX1, Genetic polymorphism, Cancer susceptibility