To prepare stable electrophoretic ink (E Ink) contains titanium dioxide particles, oil soluble red, dispersant and tetrachloroethylene (TCE), the modification of organic materials onto the particle surface was investigated. Modified particles were characterized by measurement of Fourier transform infrared spectroscopy (FT-IR) to confirm the composites and structures. The electrophoretic properties of sample in TCE were investigated by static sedimentation experiment and electrophoresis instrument. The type of organic materials used for the surface modification influence dispersibility and charge property of particles. On the whole, organic modified particles especially modified by anionic surfactant show better properties. The process conditions were investigated in detail using SDBS as the modifier. The results indicate the settle time of modified TiO₂ can last more than 200h with the response time to 30s in optimized modifying condition that the proportion of surfactant is 15% and reaction time is 1 hour which means SDBS modified TiO₂ is suitable for electrophoretic particles.