Chemical modification of clay (Laponite) particles was carried out through the plasma activation process and chemical grafting of sulfonic groups. The occurrence of the surface modification and the chemical structure of resulting products were characterized with FTIR, XPS and thermal analysis. Also, X-ray diffraction spectrometry observation of the Laponite particles confirmed the surface modification. Proposed approach provides the original method of organically modified clay particles and can be applied to the preparation of hybrid organic-inorganic nanocomposites. The application of Nafion (R)/modified Laponite hybrid membranes for proton exchange membrane fuel cells was evaluated in terms of proton conductivity, swelling degree and cell performance. By increasing the proton conductivity of the Laponite and the thermal stability of the composite membrane, the performance of fuel cell made with this type of membrane was improved. (C) 2010 Elsevier B.V. All rights reserved.