Ceramic nanoparticles (NPs) were surface modified and dispersed by in situ synthesized block copolymers. Living radical polymerization with sequential addition of monomers enables the effective coating of ceramic NPs by block copolymers. The method enables us to add stable polymer layers on any kind of NPs; therefore, it can help the mass production of polymer-coated inorganic NPs and drastically reduce the cost, without sacrificing their performance.