An analytical solution is investigated for forced convection heat transfer from a laminar plane wall jet as conjugate case. For Re >> 1, boundary layer theory is used for the investigation. The problem has been solved for two classic cases such as Pr >= 1 and Pr << 1. The conjugate model consists of considering the full Navier-Stokes equation in the fluid medium and coupling of energy equations in the fluid and the slab through the interface boundary conditions. Closed-form relations are found for Nusselt number (Nu), average Nusselt number (Nu) and conjugate interface boundary temperature (theta(b)). The effects of the Reynolds number (Re), the Prandtl number (Pr), the thermal conductivity ratio (k) between the slab and the fluid medium and the slab aspect ratio (lambda) are investigated on the heat transfer characteristics. The analytical results are compared with the full numerical results. (c) 2005 Elsevier Ltd. All rights reserved.