Organic pigment has been considered as one of the most suitable materials for the colored electrophoretic ink particles in a microcapsule type electrophoretic display, in which the electrophoretic display is consisted with the electrophoretic ink particles dispersed in the low dielectric medium. In this study, the effect of polymer encapsulation on electrophoretic properties of organic pigment nanoparticles in low dielectric medium was investigated. Blue colored organic pigments were encapsulated with poly(methyl methacrylate) via two step dispersion polymerization of methyl methacrylate with the presence of the organic pigments. Vinyl imidazole was used as a co-monomer to enhance the electrophoretic properties of the pigments. The modified particle surface was characterized by measuring zeta potential in low dielectric medium.