Purpose - The purpose of this paper is to study the mixed convection in a nanofluid along an inclined wavy surface embedded in a porous medium. Design/methodology/approach - The complex wavy surface is transformed to a smooth surface by employing a coordinate transformation. Using the similarity transformation, the governing equations are transformed into a set of ordinary differential equations and then lineralized using the successive linearization method. The Chebyshev pseudo spectral method is then used to solve linearized differential equations. Findings - The effects of Brownian motion parameter, thermophoresis parameter, amplitude of the wavy surface, angle of inclination of the wavy surface for aiding and opposing flows on the non-dimensional velocity, temperature, nanoparticle volume fraction, heat and nanoparticle mass transfer rates are studied and presented graphically. Originality/value - This is the first instance in which mixed convection, inclined wavy surface and nanofluid is employed to model fluid flow. © Emerald Group Publishing Limited.