The invention provides a separation and extraction method for 
nickel and 
cobalt in a low-grade 
sulfide mineral 
bioleaching agent through synergistic extraction. The separation and extraction method comprises the following steps: adopting a biological 
alum precipitation method to perform iron removing on the 
nickel-
cobalt-containing leaching agent, adding iron-oxidizing 
bacteria under the condition that the pH is 1.8 to 2.0, utilizing oxidation of the 
bacteria to oxidize 
ferrous ions in the leaching agent into 
ferric ions, and enabling the 
ferric iron to form 
jarosite-class 
precipitation; adopting the extraction agent P204 to perform 
impurity removing on the residual impurities in the leaching agent after iron removing to remove impurities including 
calcium, 
magnesium and the like; and using the compound extraction agent containing extraction agent P507 and Cynaex 272 to perform synergistic extraction on the leaching agent after 
impurity removing, standing for 
phase splitting for 30 min after extraction, and adding 
sulfuric acid into the organic phase and performing reverse extraction to extract out 
cobalt, so as to realize separation of 
nickel and cobalt through synergistic extraction. The method provided by the invention can reduce 
neutralization cost of pH value adjustment before extraction of the leaching agent, and omits the pH adjusting procedure when subsequent extraction 
raffinate returns back to the mineral 
pile, so as to simplify the technological process, and reduce the 
neutralization cost and nickel and cobalt entrainment losses caused in the 
neutralization process.