This paper theoretically consider steady natural convection flow of exothermic fluid with magnetic field over a asymmetrically. The flow is assumed to be laminar, viscous, incompressible and in an electrically conducting fluid. The flow is governed by momentum and energy equations. The governing steady equations are solved analytically using perturbation series method. The solutions are obtained for different values of Magnetic field (M), Porosity parameter (K), Reactant consumption parameter (?), Activation energy parameter (?) and Buoyancy distribution parameter (r). The result of temperature, velocity, Nusselt number and skin friction are obtained and discussed using line graphs.It was observed that an increase in the values of reactant consumption parameter and porosity parameter increase velocity profiles, while an increase in magnetic parameter decreases. An increase in porosity parameter and buoyancy distribution parameter, also increase heat transfer. Keyword: Free convention, Transient, viscous reactive fluid and magnetic field