Taking the advantage of the inherent chemical activity arisen from the nitrogen incorporation for nitrogen-doped carbon nanotubes (NCNTs), we have developed a facile strategy for the construction of binary Pt-Ru/NCNT electrocatalysts. Alloyed Pt-Ru nanoparticles have been directly immobilized onto the outer surface of NCNTs without pre-modification due to the nitrogen participation. The Pt-Ru nanoparticles have a high dispersion, a narrow size distribution of 2.5-3.5 nm and tunable chemical composition. These catalysts have been evaluated for methanol oxidation and show good stability and better CO tolerance than the monometallic Pt/NCNT catalyst due to the bifunctional and electronic effects. The Pt5Ru5/NCNT catalyst shows superior electrocatalytic performance to the commercial Pt5Ru5/C catalyst. The easy fabrication and excellent performance of the NCNT-based Pt-Ru alloy catalysts indicate their potential application in direct methanol fuel cells. (C) 2010 Elsevier B.V. All rights reserved.