A method for enhancing biological oxidation of arsenic-containing gold ore through potential regulation and control is disclosed. The method includes (1) subjecting the arsenic-containing gold ore tofine grinding to obtain ore powder; (2) preparing a 9K medium; (3) adding the ore powder obtained in the step (1) and thiobacillus ferrooxidans into the 9K medium prepared in the step (2), performingprimary biological leaching to obtain primary ore pulp, then adding a Fe<3+> solution to adjust the potential of the primary ore pulp, adjusting the pH of the primary ore pulp at the same time, and performing secondary biological leaching to obtain secondary ore pulp; and (4) after the secondary biological leaching in the step (3) is finished, subjecting the secondary ore pulp to solid liquid separation to obtain gold leaching slag. The method can significantly shorten the leaching period, is high in treatment efficiency and simple to operate, and can be widely used in ore enterprises of various sizes.