The effect of chemical reaction, heat and mass transfer on boundary layer flow over a porous wedge with heat radiation has been studied in the presence of suction or injection. An approximate numerical solution for the steady laminar boundary-layer flow over a wall of the wedge in the presence of species concentration and mass diffusion has been obtained by solving the governing equations using numerical technique. The fluid is assumed to be viscous and incompressible. Numerical calculations are carried out for different values of dimensionless parameters and an analysis of the results obtained shows that the flow field is influenced appreciably by the chemical reaction, the buoyancy ratio between species and thermal diffusion and suction/injection at wall surface. Effects of these major parameters on the transport behaviors are investigated methodically and typical results are illustrated to reveal the tendency of the solutions. Representative results are presented for the velocity, temperature, and concentration distributions, as well as the skin friction, rate of heat transfer and mass transfer. Comparisons with previously published works are performed and excellent agreement between the results is obtained.