The work aims to study the influence of the porosity of aluminum foam on the energy absorption properties of aluminum foam-polyurethane composites. A quasi-static compression test was carried out on the prepared aluminum foam-polyurethane composites. The stress-strain curves of aluminum foam and aluminum foam-polyurethane composites with different porosity were obtained by quasi-static compression test. The analysis showed that, the energy absorption properties of aluminum foam increased by 71.9% when its porosity decreased from 94.6% to 93%. The energy absorption properties of aluminum foam-polyurethane composites formed by aluminum foam filled with polyurethane can be greatly improved, compared with those of aluminum foam; and the porosity of aluminum foam has the negative correlation with the energy absorption properties of aluminum foam-polyurethane composites.