Hepatocellular Carcinoma (HCC) in high-incidence areas (sub-Saharan Africa, South-Eastern Asia) often contains a somatic mutation at codon 249 in TP53 (R249S). This mutation is rare in low-incidence areas of Europe and the United States. There is evidence that R249S occurs as the result of mutagenesis by aflatoxin in a context of HBV chronic infection. Here, we summarize the mechanisms of R249S formation and the possible role of p.R249S protein in HCC pathogenesis. Next, we discuss the significance of R249S as a biomarker to study the natural history of HCC and as a target for therapeutic approaches aimed at restoring wild-type p53 activity.