This study explores the effect of incorporating recycled polyethylene terephthalate (PET) into asphalt pavement mixtures. The performance characteristics were observed to determine if the mechanical properties of the resulting mixture had significantly improved. The PET-asphalt mixtures were prepared using the dry method and were then evaluated based on the Marshall flow and stability tests, as well as its volumetric properties – such as air voids, voids filled with asphalt (VFA), voids in mineral aggregates (VMA), bulk specific gravity (BSG), and maximum specific gravity (MSG). Results show that the optimum PET content in the mixture is 15% by weight of asphalt binder at 5% binder composition of the overall asphalt pavement mixture. The stability was observed to increase by 14.2% compared with the conventional mix and each sample passed the standards set by the Asphalt Institute. Based on the results, it can be concluded that at certain amounts, the addition of PET improves the Marshall properties of the pavement.