Membrane based process assumes a significant importance among all the separation practices being followed in the present time. Among the limitations faced by the membrane process, the most critical one is the bio-fouling, which results in lesser throughput as well as deterioration in membrane life. To enhance the anti-biofouling behaviour of the membrane surface, nanostructured materials offer a tremendous opportunity. One potential candidate among them is the carbon nanotubes (CNTs). With the objective of having improvement over the existing anti-biofouling tendency of polysulfone membranes, nanocomposites were developed with impregnation of both single walled as well as multi walled CNTs. The performance of the membranes was evaluated in terms of pure water permeability and solute rejection studies. The membranes were characterised using scanning electron microscopy, atomic force microscopy and contact angle studies. The anti-biofouling performance of the membrane surfaces was examined using E. Coli culture and a comparison of antibiofouling tendency obtained with the nanocomposites over the pure polysulfone membranes has been made. It was confirmed that membranes with impregnation of single walled CNTs possess better antibiofouling behaviour as compared to pure polysulfone as well as polysulfone membrane embedded with multi walled CNTs. © 2013 AIP Publishing LLC.