A novel composite of RGO wrapped Fe3O4–Co3O4 (RGO/Fe3O4–Co3O4) yolk–shell nanostructures were designed and synthesized. The composite of RGO/Fe3O4–Co3O4 shows high performance for activation of peroxymonosulfate (PMS) for organic dyes degradation. The RGO wrapping can prevents cobalt leaching in the catalytic process, meanwhile maintains high catalytic activity even after 10 cycles.