A comparison of the performance of a solid-polymer electrolyte direct methanol fuel cell (SPE-DMFC) with aqueous methanol and air mixed at the anode, and with only aqueous methanol is presented. The performance of the mixed methanol reactant and air fed anode SPE-DMFC is superior to the conventional methanol only fed anode SPE-DMFC. The experimental performance of the mixed-reactant anode SPE-DMFC are compared with results of a numerical modelling based on phenomenological transport equations for electrocatalyst layer, diffusion layer and the polymer electrolyte membrane.