2-D elasticity was employed to solve a thermal stress problem of a three layer laminated beam, in which each layer has different thermal expansion coefficient. The thermal stresses arise as a result that initially the layers of the beam were bonded at some high temperature T(H) and then quenched to some low temperature T(L). Elastic stress field can be derived and expressed in closed form by following the algorithm presented. A numerical example is presented to show that stress concentration due to this thermal effect at the ends of a laminated beam is high and steep enough to cause failure in an ultra-high carbon content and hardened steel.