Twenty two strains of Salmonella belonging to eight different serovars, namely S. enterica subsp. enterica serovar S. typhimurium, S. nchanga, S. newport, S. virchow, S. bovismorbificans, S. seftenberg, S. weltevreden and S. indiana, isolated from foods of animal origin, were tested for their cytotoxicity on MDBK and Vero cell-lines. Although all the strains were found to be cytotoxic for both the cell-lines, their cytotoxic activity varied greatly. A dose-related cytotoxic effect was observed. Polymyxin B sulphate @.25 mg/ml in PBS, pH 7.2), urea (8M in Tris-HCl buffer, pH 8.2) and cell-sonication were found to augment the release of cytotoxin.