Abstract: A disposable cat litter box comprises a bottom box portion for carrying litter material, a top box portion and a collapsible shell support structure. The bottom box portion has a bottom wall, a pair of end wals extending upwardly from the bottom wall and a pair of side walls extending upwardly from the bottom wall. The side and end walls have an inner and an outer surface. The top box portion is designed to engage the bottom box portion. The top box portion has a top wall, a pair of end walls extending downwardly from the top wall and a pair of side walls extending downwardly from the top wall. The side and end walls of the top box portion have an inner and an outer surface. The inner surface is designed to fit snugly adjacent the outer surface of the bottom box portion.