This paper is devoted to obtain non-similar solutions for the effect of viscous dissipation on the steady double diffusive mixed convection flow over a vertical exponentially permeable stretching surface. The non-linear partial differential equations governing the flow, thermal and species concentration fields are written in the non-dimensional form by using suitable group of transformations. The final non dimensional set of coupled partial differential equations is solved using the implicit finite difference method in combination with the Newton's linearization technique. The effects of various non dimensional physical parameters on velocity, temperature and species concentration fields are discussed. The presence of the suction/injection at the surface expedites the mass transfer phenomena. The numerical results in terms of the skin friction coefficient, the rate of heat transfer in terms of local Nusselt number and mass transfer rate in terms of Sherwood number shown graphically for various physical parameter involved in the problem. The present results are compared with previously published work, and these comparisons are found to be in excellent agreement. (C) 2017 Elsevier Ltd. All rights reserved.