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In order to find out if staphylococci occur in significant numbers in Korean fermented fish products, a total of 40 different fermented fish products were collected from different markers in Korean and analyzed for their physico-chemical and microbiological states. The pH, salt concentration and water activity of the products were measured and the total viable cell count and the number of Staphylococcus grown on mannitol salt agar were determined. The identification of the strains of Staphylococcus were made by API Staph Strip and MIS identification kits, and the physiological of the identified strains were further characterized by different conventional methods. The pH, salt content and water activity of fermented fish samples varied widely from 4.8 to 7.1, 7.4-28.7% and 0.77-0.84, respectively, depending in the type of product. The total viable cell count varied from 10^4-10^9 cfu/ml, and most of the samples had 10^5-10^6 cfu/ml. No correlation was found between the viable cell count and the pH, NaCl concentration and water activity of the samples. Among the 35 colonies identified as Staphylococcus strains by the identification kits, S xylosus was the most frequently occurring strain marking 17, and S. warnei was 8, S. epidermidis 4 and S. cohnuu 2. S. hominis, S. saprophyticus, S. haemolyticus and S. aureus were also identified once each. In some samples (K-3, P-6, K-8, G-5 and G-10), 2-3 different species of Staphylococcus were found. Considering the region of sampling, among the 10 samples from Kunsan 5 were identified as S. warneri. while in the other region S. xylasus was predominant. Although the physiological characteristics of the identified strains were generally consistent with those in Bergey´s Manual, some discrepances were also observed. All the strains were highly salt tolerant, growing in the media containing over 18% NaCl. All the strains were except S. aureus (G-11) showed negative in hemolysis activity, plasma congulation and DNase tests. All the strains including S. aureus (G-11) showed negative in enterotoxin test.
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