Abstract: According to the features of a certain refractory silver concentrate, such as high copper content, complex embedding station, low rate of conventional technology leaching, this paper proposes the leaching process of ammonium sulfate pretreatment －leaching slag －grinding -free at the first stage －grinding at the second leaching stage, and studies the intensification leaching mechanism.The test result indicates that this process can get the leaching rate of more than 74 % without increasing grinding cost and cyanide consumption, which is 9 % higher than the site index with practical significance.