Abstract. This study aimed to evaluate the permanent deformation and aging conditions of BatuPahat soft clay-modified asphalt mixture, also called BatuPahat soft clay (BPSC) particles; these particles are used in powder form as an additive to hot-mix asphalt mixture. In this experiment, five percentage compositions of BPSC (0%, 2%, 4%, 6%, and 8%) by weight of bitumen were used. A novel design was established to modify the hot-mix asphalt by using the Superpave method for each additive ratio. Several laboratory tests evaluating different properties, such as indirect tensile strength, resilient stiffness modulus, and dynamic creep, was conducted to assess the performance of the samples mixed through the Superpave method. In the resilient modulus test, fatigue and rutting resistance were reduced by the BPSC particles. The added BPSC particles increased the indirect tensile strength. Among the mixtures, 4% BPSC particles yielded the highest performance. In the dynamic creep test, 4% BPSC particles added to the unaged and short-term aged specimens also showed the highest performance. Based on these results, our conclusion is that the BPSC particles can alleviate the permanent deformation (rutting) of roads.