The ability was studied to use Pseudomonas Japonica bacteria’s culture in the cycle of the cooper-molybdenum collective ore concentrate selection with the view of xanthate desorption from the minerals surface. The influence was studied of microorganisms on the surfaces of a copper and molybdenum sulfides by means of measurement contact angle and photoelectron  spectroscopy method. Reducing xanthate concentration on the surfaces sulfides was shown, and, as consequence, hydrophilization minerals increases.