The new strain Bacillus strain B2 isolated from the soil contaminated by the trace element vanadium was evaluated for its ability to decolorize textile dye Orange G,Reactive black 5,Ethyl Green,and Reactive blue 4.Maltose (5gl-1) was the better electron donor,while ferric citrate (20 mM) were the better electron acceptors for this strain to decolorize dye under anaerobic conditions.This strain could decolorize these above mentioned dyes (200 mg l-1) under anaerobic conditions,and the best initial color removal was Ethyl Green.