Vascular invasion is one of the most important prognostic factors for patients with hepatocellular carcinoma (HCC). The objective of the current, retrospective study was to determine the associations of ascites and hepatitis B viral factors (HBeAg and anti-HBe status and HBV DNA levels), as well as tumor-related factors (size, tumor number, grade, and location) with micro- or macroscopic vascular invasion in patients with HCC that developed as a result of hepatitis B virus (HBV)-related cirrhosis. A total of 336 consecutive patients were included. Potential factors associated with micro- or macroscopic vascular invasion were analyzed by logistic regression. Ascites were more commonly detected in patients with micro- or macroscopic vascular invasion, and the presence of ascites was independently associated with vascular invasion. Among patients with mild-to-moderate or severe ascites, the odds ratio for macroscopic vascular invasion was 4.83 (95 % confidence interval [CI] 2.29-10.16) and 11.87 (95 % CI 4.53-31.07), respectively. Similarly, the presence of ascites was associated with microscopic vascular invasion (OR 5.00; 95 % CI 1.23-20.31). In contrast, hepatitis B viral factors were not significantly associated with vascular invasion. The presence of ascites was associated with vascular invasion in patients with HBV-related cirrhotic HCC. Thus, patients with ascites, vascular invasion should be considered and more frequent surveillance should be performed after curative treatment.