Li2Ru0.6Mn0.4O3/Graphene oxide(GO) composite material is obtained by mixing GO and the solid-state prepared Li2Ru0.6Mn0.4O3. The microstructure， morphology and electrochemical performances of product are analyzed by X-ray diffraction (XRD)， scanning electron microscopy (SEM)， transmission electron microscopy (TEM)， energy dispersive spectrometer (EDS) and electrochemical tests. Mildly oxidized graphene oxide mixing is found to improve the battery performance by enhancing the conductivity and protecting the cathode surface from undesired reactions with the electrolyte. The electrochemistry results show that the material exhibits better rate capacity than that of Li2Ru0.6Mn0.4O3 since the composite GO demonstrates the enhanced electronic conductivity. Accordingly， Li2Ru0.6Mn0.4O3/GO exhibits 87.5% capacity retention after 200 cycles in the cycling test， and at a large current of 5 C， Li2Ru0.6Mn0.4O3/GO is able to deliver 95% of the 0.1 C capacity.