A numerical analysis has been carried out to study magnetohydrodynamic boundary layer flow, heat and mass transfer characteristics on steady two-dimensional flow of an electrically conducting fluid over a stretching sheet embedded in a non-Darcy porous medium in the presence of thermal radiation and viscous dissipation. The governing partial differential equations are convected into a system of nonlinear ordinary differential equations by similarity transformation and are solved numerically by using the Successive linearisation method, together with the Chebyshev pseudo-spectral collocation method. The effects of various parameters on the velocity, temperature, and concentration fields as well as on the skin-friction coefficient are presented graphically and in tabular forms.