||Since boron nitride nanotubes (BNNTs) have been excellent electrical, thermal and mechanical properties, they have been of interest for a wide range of potential applications such as piezoelectric materials, reinforcement of materials and electrothermal insulation materials. For practical use of BNNTs, it is rather good for them to disperse in aqueous solution due to convenience of handling. However, it is still difficult to make a homogenous and stable BNNT dispersion in aqueous solution due to strong van deer Waals interaction and hydrophobic surface. To solve these problems, we used cetyltrimethylammonium 4-vinylbenzoate (CTVB) surfactant, which has polymerizable counterions. The BNNT was mixed with CTVB surfactants, followed by ultrasonication to disperse it in aqueous solution, and then polymerization of surfactants for stable dispersion. The BNNT/CTVB dispersion is highly stable in aqueous solution for a few weeks and is re-dispersed even after freeze dry.