Diabetes mellitus (DM) increases the risk of developing hepatocellular carcinoma (HCC), and how DM affects the prognosis of HCC have not been elucidated. The aim of this study was to compare clinicopathological characteristics and survival between hepatitis B virus (HBV)-related HCC patients with and without DM and to determine risk factors for overall survival after hepatectomy. Among 474 patients with HBV-related HCC, 119 patients had DM. Patients were divided into the diabetic group and nondiabetic group. The short-term and long-term outcomes were evaluated by using propensity score matching analysis. After 1:2 propensity score matching, there were 107 patients in diabetic group, 214 patients in nondiabetic group. The proportion of vessels invasion were higher in diabetic group. The overall survival rate in the diabetic group was 44.7% at 3 years, which was lower than that in the nondiabetic group (56.1%, P = .025). The multivariate analysis indicated that fasting blood glucose >7.0, capsular invasion, microvascular invasion and satellite were independent risk factor of poor prognosis in HCC. DM dose affect the recurrence-free survival and overall survival in HBV-related HCC patients after hepatectomy. One of the more significant findings to emerge from this study is that DM induced higher proportion of major vessel invasion in HCC patients implied unfavorable prognosis.