A Bacillus sp. isolated by 4-hydroxybenzoate enrichment culture technique is capable of utilizing 3-hydroxybenzoate as the sole source of carbon and energy. The organism degraded 3-hydroxybenzoic acid through the intermediate formation of protocatechuic acid. 3-Hydroxybenzoate 4-hydroxylase, protocatechuate 3,4-dioxygenase and protocatechuate 4,5-dioxygenase activities were shown in cell-free extracts. The formed protocatechuate is metabolized through both the ortho and meta cleavage pathway.