In this paper, the steady fully developed mixed convection flow of a nanofluid in a channel filled with a porous medium is presented. The walls of the channel are heated by a uniform heat flux and a constant flow rate is considered through the channel. The equations of the problem are made non-dimensional and are observed to depend on the dimensionless parameters, namely the mixed convection parameter lambda, the Peclet number Pe. the inclination angle of the channel to the horizontal gamma and the nanoparticle volume fraction phi. The effects of these parameters on the fluid and heat transfer characteristics are in detail discussed for three different nanofluids as Cu-water, Al2O3-water and TiO2-water. (C) 2011 Elsevier Ltd. All rights reserved.