A composite of highly dispersed Pt-RuO u-SnO v nanoparticles (NPs) on a mesoporous carbon CMK-3 framework was synthesized. The resulting composites of Pt, RuO u , SnO v , and CMK-3 were designated P w R x S y /C3, and their microstructures and compositions were systematically characterized using a variety of techniques. The Pt-based NPs have average particle sizes of 2-8 nm and were well dispersed in the pore channels of the CMK-3 host. The methanol oxidation reaction (MOR) activity of the catalysts was investigated as a function of the Sn mass fraction. The electrochemical activity for the MOR improved with increasing Sn content in the Pt-Ru-Sn/CMK-3 composite. In short, MOR activity, CO tolerance, long-term stability, cyclic durability, and cost performance of our proposed composition were significantly improved, which renders efficient routes to developing catalysts for direct methanol fuel cells.