Abstract: A new technology of styrene grafting surface modification of titanium dioxide is introduced. The main technological parameters have been studied, and the optimal combination of the parameters has been obtained. The modification mechanisms were analyzed that the process of styrene grafting surface modification of titanium dioxide is essentially a combination of negative ion polymerization and free radical polymerization, there is C-O bonds create on the surface of modified titanium dioxide. Whereas the mechanical-chemical effects caused by stirring mill, the chemical effects caused by initiating agent, the external and internal heating can all promote the modification process.