Hepatocellular carcinoma (HCC) is characterized by increased oxidative stress and the production of 8-hydroxy-2'-deoxyguanosine (8-OHdG), which is one of the main mutagenic modifications of DNA by oxidative stress. We analyzed the association of 8-OHdG with post-operative survival and revealed that low levels of 8-OHdG are associated with significantly shorter survival time. Moreover, levels of 8-OHdG were associated with HCC characteristics, including tumor size, tumor quantity, clinical staging, Child classification, portal vein thrombosis and ascites. These results suggest that oxidative damage is a useful prognostic marker in HCC when other clinical characteristics are present with 8-OHdG.