Abstract: Four bacterial strains have been isolated for their ability to growth on dibenzothiophene (DBT), dibenzothiophene sulfone (DBTO2). The results show that different bacteria strains oxidize the DBT to different products through different pathways. R-6 and R-16 metabolize DBT to DBTO2 and HBP; they are identified as species of Bacillus brevis and Bacillus sphaericus. For long time storage, R-9 identified as Nocardia globerula oxidizes DBT to DBT-sulfone (DBTO2) and benzenamine n-phenyl. The optimum temperature and pH for growth of R-16 are 32℃ and 7.02 respectively. The pH of broth decreases during the processes.