The objective of this study is to investigate the mechanical behavior of polyurethane foam sandwich panels under three-point bending tests by varying the span length and core thickness of the specimens. Theoretical models based on sandwich panel mechanics and classical beam theory are presented to support the analysis.The experiments were conducted to examine the relationship between the geometrical configuration of the sandwich panels and their failure mechanisms. The static bending tests revealed several collapse modes depending on the support span and core thickness. Observed failure modes include indentation beneath the loading roller, delamination between the core and the upper face sheet, and core shear.The effects of core thickness and span length on the maximum static load and bending stiffness were also analyzed. It was found that the span length has a significant influence on the failure modes of the specimens.