Abstract: The polysaccharide content in the bacterium HQ0211 lysate was determined by phenol-vitriol method, from which some optimal values were given including the lyric time 25 min, adsorption wavelength 430 nm and cooling time 10 min. In the test using the leaching bacterium HQ0211 to adsorb/oxidate the refractory As-bearing gold ore, it was found that the polysaccharide of bacterium cell changes with the potential of solution. When the potential is 480~572 mV and 638 mV, the polysaccharide contents of free bacterial cells in solution and of bacterial cells adsorbed on grains of As-bearing gold ore are 0.033~0.123 mg/mL and 5.3~8.9 mg/g, 1.155 mg/mL and 57.5 mg/g, respectively.