Herein, MnO2@SiO2/C was produced from rice husk derived SiO2/carbon composite and MnO2 via hydrothermal method. The nanostructure gave good microstructural, morphological properties with highly catalytic properties. The hybrid catalyst comprising of MnO2@SiO2/C nanocomposite-supported gold nanoparticles was successfully fabricated by the novel solid grinding and tested for CO oxidation's application. MnO2 nanoballs are 5 - 8 nm in diameter with a shell thickness of 1 nm, packing with laminar [MnO6] unit cells. The as-prepared gold catalysts containing 2wt% of Au loading, exhibited 50% CO conversion and a high specific activity of 0.21 mol(CO) g(Au)(-1) h(-1) at 38 degrees C. Graphic Abstract MnO2@SiO2/C nanocomposite-supported gold nanoparticles were prepared by solid grinding using a non-volatile organogold(III) complex and rice husk. The catalysts showed high activity for CO oxidation. [GRAPHICS] .