The expression of the oncogene c-erbA was studied in six hepatocellular carcinoma specimens and normal hepatic tissue. Total RNA isolated from these samples was analysed by Northern as well as slot blot hybridisation to a radioactive c-erbA probe. When compared to normal tissue, expression in the tumour and tissue adjacent to tumour was markedly elevated. These results suggest that overexpression of c-erbA is related to hepatocarcinogenesis. Southern blot analysis of DNA from the tumours gave no evidence of c-erbA rearrangements.