Night soil has been aerobically digested effectively and malodorlessly at Inacuo Sanitation Center facility. In 1991, microorganisms in the digestion tanks were isolated, and 92-98% of them was Bacillus sp. On the basis on the biochemical characteristics and GC - contents, species of 32 strains of them were identified to be B. thuringiensis (12 strains), B. megaterium (1 strain), B. pumilus (16 strains) and B. subtilis (1 strain) . Strains identified to be B. thuringiensis showed the solubilizable ability of starch and the usable ability of ammonia as the source of nitrogen like B. megaterium, while strains identified to be B. pumilus showed to solubilize cooked meat, and to use nitrate ion like B. subtilis.