The microbial flora of the kusaya brine was studied in samples obtained from manufacturers in Niijima and Oshima Islands. The classification of bacteria at the genus level was performed on 144 strains from Niijima Island and 107 strains from Oshima Island. No significant difference in the bacterial flora was observed between these brines, though molds were isolated only from Niijima samples. Bacteria of genus Corynebacterium (about 56% of total isolates) which formed minute colonies on nutrient agar plate were the most predominant in the brine followed by bacteria of genus Pseudomonas (about 22-37% of total isolates). As the characteristic organisms in the brine, bacteria of genus Spirillum were isolated from all samples in small numbers.