One great challenge in the development of noble metal nanoparticles (NPs)/carbon nanotubes nanohybrids as fuel cells electrocatalyst is to explore rationally functionalizing CNTs method for dispersion and stability of noble metal NPs catalysts with better electrocatalytic performance. Here we report a facile strategy to fabricate a carboxymethyl chitosan functionalized CNTs (CMC-CNTs) and demonstrate its application as a promising catalyst support material for direct methanol fuel cells. The developed route rationally utilizes the excellent water-solubility and abundant carboxyl (-COOH) functional groups of the CMC-CNTs as a superior supporting material for growing and supporting PtRu NPs. For methanol electrooxidation, the as-prepared PtRu NPs/CMC-CNTs nanohybrid has extremely large electrochemically active surface area (ESA) and exhibits better electrocatalytic activity and stability than PtRu NPs/CNTs catalyst. This provides a facile approach to synthesize CNTs-based nanoelectrocatalysts for high performance energy conversion devices in the future. Copyright (C) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.