The natural convection fluid flow on the effect of variable thermal conductivity on heat and mass transfer with chemical reaction, porosity and buoyancy force distribution is investigated. The nonlinear partial differential equations together with the boundary conditions are reduced to dimensionless form which are solved using perturbation technique. The effects of various parameters associated with flow like magnetic field M, mass Grashof number Gc, Schmidt number Sc, buoyancy force distribution R, mass buoyancy Rc, porosity Da, chemical reaction Kr, and variable thermal conductivity λ are studied with the help of graphs. It is observed that, the velocity increase with increasing Gc or M and the temperature increase with increasing R or λ and the concentration decreases with increasing Sc or Kr.