In this study, the flow and heat transfer characteristics of two heated square cylinders in a tandem arrangement near a wall is investigated. The numerical computations are carried out by solving the unsteady two dimensional Navier-Stokes and energy equations. A fractional step method with Crank-Nicholson schema was employed to the convective and the viscous terms of the equations. At the inlet, fully developed laminar boundary layer is employed for longitudinal velocity over the plane wall while transverse velocity set to zero. The simulations are performed for Prandtl number (Pr) of 0.71 and Reynolds number (Re) of 150 where the flow is considered two dimensional. The flow field characteristics and heat transfer depend not only on the ratio of the space between the cylinders (L/D) but also on the distance between the cylinder center and the wall (G/D). The vorticity and isotherm curves are generated and discussed for various L/D and G/D ratios to clarify the connection with flow and heat transfer characteristics. When the cylinders are within the boundary layer formed on the plane wall, the large difference between the velocities at the upper and lower side of the cylinders leads to noticeable variation at the flow and heat transfer characteristics.