Magnetohydrodynamic fully developed mixed convection flow of a viscous incompressible electrically conducting fluid confined to a vertical channel with asymmetric heating of the wall, is studied. It has been shown that a reversed flow occurs due to asymmetric heating of the wall when the magnitude of the buoyancy parameter Gr exceeds a certain threshold value. The limiting cases of the MHD free and forced convection flow are analysed. A qualitative discussion for the occurrence of a flow reversal is given in this paper. It is interesting to note that in the higher buoyancy the bulk temperature of the MHD flow exceeds the value 1 when rT < 1.