The copper anode slime intermediate material gold separating residue was used as raw material and a new hydrometallurgical process of high purity sliver powder preparation was proposed, the process comprising following steps: sodium sulfite leaching silver, acidification deposit silver, purification and sliver reduction. The reaction mechanism and optimum conditions of process were investigated. Under the optimum conditions, the leaching rate of silver reaches 98.4%, the removal rates of impurity element Pb and Te in silver chloride reach 97.2% and 96.7%, respectively, and the direct recovery rate of Ag reaches 98.1%. The chemical composition, morphology and crystal structure of product were analyzed by optical emission spectrometry (OES), scanning electron microscopy (SEM) and X-ray diffractometry (XRD), respectively. The results show that high purity 99.995% silver powder with uniform morphology and particle is prepared.