Functionalization of Carbon Nanotubes Kajal Chaudhari, Rajnandini Tambade, Dr. S.H. Pisal* Department of Physics, S.M.Joshi College Hadapsar Abstrat-It is well known that carbon nanotubes do not represent significant reinforcement for composite but once functionalized it shows interesting new properties. Multi Wallled Carbon Nanotubes synthesized using arc discharge method were initially treated with mixture of 3:1 (V/V) of concentrated H2SO4/HNO3.This acid treatment introducing the carboxylic group at defect sites and end of CNTs. Motivation- For many application uniform and stable dispersion of CNTs is required. But pristine CNTs are insoluble in most organic solvent and aqueous solution. They tent to aggregate as result of Vander Waals interaction. Functionalization overcome such problems. It increase solubility of CNTs, improve the chemical reactivity and enhance the interaction with other compound in hybrid material. Scheme of fnctionalization Conclusion- XRD confirms graphitic nature of CNT and their Functionalization.