The possibility of the utilization of soybean curd residue, okara, for the production of a lipopeptide antibiotic, iturin A, in solid state fermentation (SSF) by Bacillus subtilis NB22 was investigated. Okara is a by-product of the tofu manufacturing process, now treated as an industrial waste and disposed of mostly by incineration. Dehydrated okara, with improved transportability and preservability, could be used as effectively as the fresh, intact okara for SSF by B. subtilis NB22 for the production of iturin A.