In order to reduce the environmental pollution caused by acid mine drainage,and provide potential microbiology resources for mine drainage treatment, an acid tolerant sulfate educing bacteria strain SRB1was isolated from soil,and its characterization of reducing sulfate and cadmium removal were discussed. The results showed that the strain had high desulfurization and cadmium removal potential, and its lowest tolerant pH value, optimum temperature and maximum Cd²⁺ concentration were 3.7, 35℃ and 40mg/L, respectively. Under the condition of COD/SO₄^2- ≥ 2, Cd²⁺ concentration ≤ 30mg/L, the cadmium removal rate can reach more than 99%. In the high concentration of Cd²⁺ and SO₄^2- system, the strain had strong adsorption on Cd²⁺, Cd²⁺ can be decreased from 50mg/L to 15.5mg/L, the adsorption rate reached 58%. Using secondary culturing SO₄^2- might be reduced from 1.5g/L to 0.04g/L, the desulfurization rate reached 97.3%, and the Cd²⁺ concentration almost decreased to 0. TEM, FTIR, SEM characterization showed that the cell morphology of the strain was changed under cadmium stress, the infrared absorption peak was changed obviously before and after adsorption, and the precipitated particles contained crystalline CdS.