Purpose -The paper aims to consider non-viscous, laminar mixed convection boundary-layer flow over a horizontal moving porous flat plate, with chemical reaction. Design/methodology/approach -The governing equations are expressed in non-dimensional form and the series solutions of coupled system of equations are constructed for velocity, temperature and concentration functions using numerical method. Findings -The investigated parameters are: buoyancy parameter, chemical reaction parameter, order of chemical reaction, Prandtl number and Schmidt number. Originality/value -The partial differential equations are transformed to ordinary differential equations. The method of one parameter continuous group theory is used for this transformation.