Cells isolated from rainbow trout fins Oncorhynchus mykiss, Walbaum were propagated and subcultured a s fibroblast-like. Viral haemorrhagic septicaemia virus (VHSV) replicated in the cultured fin cells as demonstrated by fin cell lysis, posihve immunofluorescence with polyclonal anti-VHSV, and Increase in titre as measured by either infection of f~s h cell lines or by sandwich ELISA with anti-VHSV monoclonal antibodies. The possible use of these fln cell cultures as VHSV-antigen presenting cells for immunological studies is briefly discussed.