Carbon black used for fuel cell catalyst support system is modified using nitrogen and allylamine plasma and its effect on the carbon surface and fuel cell performance are reported. Custom designed radio frequency tumbling plasma reactor is used to surface modify the carbon black. Boehms Titration method, XRD and TEM are performed to confirm and analyze the effects of plasma treatment on the carbon surface. In the fuel cell electrochemical study both the nitrogen and allylamine modified catalyst support system exhibited better discharge performance than the control system. Nitrogen moieties on the carbon surface helped to decrease the particle size of catalytically active sites and provided good anchoring of Pt to the surface thereby resulted in increased electrochemical performance in the fuel cell evaluation. Copyright (C) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.