A numerical computation has been carried out, to investigate the effects of Soret and Dufour numbers on mixed convective heat transfer flow for a steady, two dimensional, incompressible, electrically conducting viscous fluid over a vertical plate in a porous medium under the influence of magnetic field with variable fluid properties. The physical governing equations for the fluid flow represents in the nonlinear PDE's regime, which are reduced into a system of ODE's using similarity transformation. The numerical computation of shooting technique is adopted to analyze the nature of velocity, temperature, concentration fields, skin friction, heat and mass transfer coefficients graphically for Uniform permeability (UP) as well as Variable permeability (VP) and illustrated for various non-dimensional parameters of the physical model. The results of the numerical scheme are validated and a numerical comparison has been done for a particular case with the available literature in the absence of few physical parameters and found that in good agreement. © 2018 Trans Tech Publications, Switzerland.