An optimized chemical separation and purification method for measuring Cu and Zn isotopic composition in cobalt-rich crusts was established.A new type of anion exchange resin,AG MP-1M,was successfully applied in the chemical separation of Cu,Co,Fe and Zn from cobalt-rich crusts.Cu,Co,Fe and Zn were separated using 8.2 mol/L HCl+0.01% HF+0.001% H2O2,2 mol/L HCl+0.001% H2O2 and 0.5 mol/L HNO3 as eluents.The recoveries for Cu and Zn were both close to 100%.No mass fractionation during the chemical separation procedure was observed.This method could be applied in the separation of Cu and Zn in Co-rich crusts for high-precision isotope analysis using MC-ICP MS.