A total of 118 Staphylococcus aureus strains isolated from routine sampling, samples from food poisoning outbreaks and human clinical specimens were examined for the production of enterotoxins A, B, C, D and E. The toxic properties of strains were compared with other biochemical characteristics and with the sensitivity to antibiotics. Of the total strains examined, 17.8% (21 strains) produced enterotoxins, and of the toxigenic strains, 81% (17 strains) produced just one type of enterotoxin and 19% (4 strains) two types. Enterotoxin A production was found in 52.4% strains, the other enterotoxins detected in decreasing order of frequency were: C; B; AD; D; AB and BD. All the strains examined produced catalases, coagulases, thermonuclease and fermented glucose; 81 and 89.7% for toxigenic and non-toxigenic strains, respectively, fermented mannitol; 47.6 and 54.6% hydrolyzed casein and 47.6 and 52.6% gelatin; 85.7 and 92.8% produced yellow or orange pigment. Mixed acid fermentation was carried out in 100% and in 96.9%; acetoin was produced by 57.1 and 47.4%; one or more hemolysins were released by 85.7 and 92.8% of the toxigenic and non-toxigenic strains, respectively. Sensitivity to antibiotics was widespread among all the strains. No relation was found between enterotoxin B production and methicillin and tetracycline resistance. Neither the biochemical properties nor the sensitivity to antibiotics has been shown to correlate reliably with toxin production.