The work aims to study the compressive properties of aluminum foam-polyurethane (AF-PU) composites through the quasi-static compression experiments, and investigate the rule of effect of relative density of aluminum foams (AF) on the energy absorption properties of the composites. AF-PU composites were first prepared with related instruments and materials, and then the quasi-static compression experiments were carried out with related instruments. The AF-PU composite material was subject to the quasi-static compression experiments by related instruments, the corresponding stress-strain curves were calculated, and the corresponding energy absorption-strain curves were obtained by calculation. When the relative density of aluminum foam increased from 5.6% to 6.7%, the yield strength of the overall composite in-creased by 22.18%. During the compression process, when the compressive strain of the composite was 0.8, the total energy absorption of the overall composite increased by 70.08%. The energy absorption properties of AF-PU composites intensify with the increase of the relative density of AF.