AbstractThis study aims to evaluate and characterize the properties of modified asphalt cements exposed to high temperature. The Acrylate Styrene Acrylonhrtilrei (ASA) polymer and nano aluminum oxide (Al2O3) nanoparticles were added to the base asphalt cement with concentrations of 3, 5 and 7% of the weight of asphalt. The storage stability, viscosity, frequency sweep and MSRC test were considered for evaluation. The results demonstrate that the addition of ASA polymer and Al2O3 nanoparticles content have a great influence on the rheological properties of the asphalt cement at high temperatures. Additionally, it is clear that the storage stability of modified asphalt cements with ASA polymer and Al2O3 nanoparticles has good compatibility among the asphalt cement and the modifiers. Moreover, the complex modulus (G*) improves as the concentration of both modifiers increases. The improvement was 63.70% for 5% ASA polymer, and 71.12% for 5% Al2O3 at 75°C. Moreover, the modified asphalt cements demonstrates great resistance to high temperatures rutting, as the enhancement was up to 80 and 59% for 5% concentration of ASA and Al2O3. The modification of asphalt cements provides increasing the creep recovery up to 69.23 and 62.53%. It was found that the usage of ASA polymer and Al2O3 nanoparticles is able to mitigate asphalt cement problems at high temperatures, and 5% is considered as the optimum content of both modifiers.