Loss of the RASSF2A expression induced by methylation-mediated silencing has been reported in several human cancers, but the methylation status of RASSF2A in hepatocellular carcinoma (HCC) is rarely studied so far. In this study, we investigated the RASSF2A expression and its methylation status in a cohort of 45 hepatitis B virus-associated HCC tissues and their adjacent non-carcinoma tissues by using RT-PCR and MS-PCR. Promoter methylation of RASSF2A was found in 31 (68.9%) out of 45 HCC tissues and 12 (40%) out of 30 adjacent normal tissues, respectively (P<0.05). The methylation status of PASSF2A was closely associated with the loss of RASSF2A expression and elevated serum alpha-fetoprotein level, but not significantly with clinical stage, hepatic fibrosis and K-ras mutation. It was concluded that aberrant methylation of the RASSF2A gene with the subsequent loss of RASSF2A expression plays an important role in the pathogenesis of HCC.