Abstract: Cadmium ions were added into the culture medium to make certain the cadmium-resistance of ore bioleaching bacteria and the influence of cadmium ions on their growth. The results showed that different concentrations of cadmium ions affect differently the growth and activity of the bacteria. If the concentration in the liquid medium is lower than 0.1 mmol/L, it is nutrient to the strain we selected and expedites its growth, whereas the further increasing concentration will inhibit its growth. Ore bioleaching bacteria have a good ability to resist cadmium and they remain growing with high activity kept on even if the concentration of cadmium ions is up to 8 mmol/L. However, if the concentration is 10 mmol/L, the growth of ore bioleaching bacteria will be inhibited.