Aim of presented study was to compare plateau stress in honeycomb structures under out-of-plane load calculated using Wierzbicki formula with numerical simulations validated using expe-rimental trials. ALUBOND® Alucore honeycomb structure was examined. The results of theoreti-cal, experimental and numerical investigation are reported. Two methods of modeling core be-havior were evaluated using simulations. Full core geometry and simplified Y-shaped element we-re analyzed. Both approaches were compared with experimental out-of-plane compression tests. Aim of the study was to determine the influence of core geometrical parameters on obtained pla-teau stress value. Various foil thicknesses and cell sizes were studied numerically. The results showed, that initial and final deformation mode strongly depends on the geometry of the honey-comb structure. Force required to crush the core grew with increase of wall thickness, and decrea-sed with increase of cell size. Calculations were performed using an implicit integration scheme implemented in the LS-DYNA software. Research showed the presence of plateau relationship between stress and geometric dimensions and structure response. Good agreement between results obtained by all methods was achieved. Basing on the results, conclusions concerning modeling honeycomb materials were drawn.