The paper deals with the vibration and thermal buckling behavior of sandwich beams with composite facings and viscoelastic core. Sandwich plate and beam elements are compared in this context. Each composite laminate is modeled as an equivalent single layer. Steady state temperature field is assumed. The formulation is a decoupled thermo mechanical formulation where in the temperatures in the domain of the beam are calculated first and made use in further calculations. The effect of fiber angle, the effect of aspect ratio and the effect of the core thickness on the performance of the elements is studied. The study reveals that there is a considerable difference between the predictions of plate and beam elements for some fiber angles. © 2006 Elsevier Ltd. All rights reserved.