Graphene oxide was modified using long-chain silicone. The modified graphene oxide (MGO) was obtained with a broader spacing of layers (1.45nm) which means more beneficial to polysiloxane entering into the laminates of MGO sheets. Then, MGO sheets were combined with polysiloxane which synthesized without any organic solvent to prepare nanocomposite coatings via cross-linking curing reaction. The solid content of polysiloxane can be reached up to 86%. Due to strong interfacial interaction and synergistic reinforcing between MGO sheets and polysiloxane, when blended with 1.00wt% of MGO, the micro-hardness and elastic modulus of coating films were increased by 57% and 24% comparing with pure polysiloxane coating film, respectively. Subsequently, a 48% improvement of macro-scratch resistance can be achieved. Simultaneously, MGO/polysiloxane coating film showed excellent wear resistance due to the unique two-dimensional geometry and low frictional coefficient of MGO sheets at work in homogeneous dispersion system.