The potential applications of carbon nanotubes are reviewed in this paper. With the development of modification and purification of carbon nanotubes, the scope of carbon nanotubes applications is expanded greatly. This paper pays attention to the modification and dispersion of multi-walled carbon nanotube (MWNTs). The results show that the acid treated MWNTs are highly pure and the surface of treated MWNTs is rough comparably. In addition, treated MWNTs are homogeneously dispersed without any surfactants present in organic solvents of acetone, toluene, and ethanol; the dispersive stability of carboxylic MWNTs dispersions is investigated over 2 weeks.