Abstract: In order to recover cobalt from the Congo cobalt-containing copper oxide ore, the process of reduction leaching-impurity removal-cobalt precipitation with active magnesium oxide has developed. The effects of adding methods and dosages of sodium metabisulfite, leaching reaction time, impurity removal reaction time, the adding methods and dosages of active magnesium oxide, precipitation reaction time were studied. The results showed that under conditions of particle size 74 μm 70%, pulp density 33%, pH 1.5~1.8, sodium metabisulfite 8 kg/t ore, added 30 minutes after sulfuric acid, reaction time 5 h, the cobalt leaching rate is 90.38%; After copper SX, limestone and lime were used to remove impurities from raffinate, 6 hours at room temperature, and the endpoint pH was controlled at about 5.8, the copper precipitation rate was 90.51%. The iron precipitation rate was 99.23%, the cobalt precipitation rate was 7.39%.The precipitated residue was returned to the leaching process to recover copper and cobalt; The solution after impurity removal were sent to precipitate cobalt by active magnesium oxide. The active magnesium oxide was added within 5 minutes of emulsification. Under conditions of the mass ratio of MgO and Co 1.03, reaction time 5 h, the cobalt precipitation rate was 90.13%.The cobalt hydroxide precipitation meets the requirements of the industry's secondary product standards.