In this paper, the numerical investigation of double-diffusive mixed convection with magnetohydrodynamic flow in an enclosed cavity is presented. The uniform temperature and concentration are imposed along the vertical walls and the horizontal walls which are considered as insulated. The flow behaviour is analysed for two different conditions. In first case, the top wall moves towards left at a constant velocity (Uo), while the other walls remain stationary. In the second case, the top wall moves towards right with constant velocity (Uo), while the other walls remain stationary. The convective flux in the transport equations is discretized using finite volume technique with third-order deferred quadratic upwind interpolation for convection kinematics scheme at the inner nodes and the second-order central difference scheme at the outer nodes. The pressure and velocity terms are coupled by SIMPLE algorithm. The present numerical simulation is compared with the reported literature and is found to be in good agreement. The Hartmann number (1 ≤ Ha ≤ 25), Lewis number (1 ≤ Le ≤ 50) and aspect ratio (1 ≤ A ≤ 2) are varied over a wide range to analyse the non-dimensional horizontal (U) and vertical velocities (V), stream line contours, temperature and concentration gradients. The present analysis is carried out at constant Buoyancy ratio (N = 1) and Prandtl (Pr = 0.7), Richardson (Ri = 1.0), Darcy (Da = 1.0) and Reynolds (Re = 100) numbers. The effect of Ha, Le and A on the average Nusselt (Nu) and Sherwood (Sh) numbers is also presented. © 2015, King Fahd University of Petroleum & Minerals.