Effects of a conductive wall on natural convection heat transfer in a rectangular enclosure filled with porous media sandwiched by two finite thickness walls is studied numerically in this article. The horizontal heating is considered, where the vertical walls heated isothermally at different temperatures while the horizontal walls are kept adiabatic. The general flow model known as the Brinkman-Forchheimer-extended Darcy mode is used in the mathematical formulation for the porous layer and finite difference method is applied to solve the dimensionless governing equations. The governing parameters considered are the Rayleigh number (10 3 ≤ Ra ≤ 10 6), the wall to porous thermal conductivity ratio (0.1 ≤ Kr ≤ 10), the Darcy number (10 −6 ≤ Da ≤ 1), the porosity of the porous region (0.2 ≤ ϵ ≤ 0.9), and the ratio of wall thickness to its height (0.25 ≤ D ≤ 0.375). The results are presented to show the effect of these parameters on the fluid flow and heat transfer characteristics.