In the present work, energy attenuation properties of sandwich structures are investigated. In addition to the conventional sandwich structures, an intelligent concept was included by integrating the structures with a non-Newtonian material. The non-Newtonian material shows shear thickening effect under loading. Due to its thickening behavior, it contributes to the energy suppression upon loading. For this reason, the non-Newtonian material was filled into the holes drilled in the core material of the sandwich composites. The core material was extruded polystyrene (XPS) foam and the face sheets were made from aluminum alloys. From the results, energy attenuation of the sandwich structures shows enhanced properties by incorporating the non-Newtonian material into the composites.