Due to the failure of asphalt pavements brought on by factors such traffic loads and the properties of hot mix asphalt (HMA) on asphalt pavement combined with the need for new building materials, research into better techniques to improve the properties of asphalt pavement for better performance is crucial. The Marshall Mix design method is used in this study's experimental approach to investigate the modification of a dual blend of polyethylene and periwinkle shell ash in the improvement of asphalt pavement while taking into account the Retained Marshal Stability for both soaked and unsoaked conditions. The results obtained shows that the threshold mix to obtain the optimum stability, density and flow corresponds to 19% polyethylene by weight of binder at optimum binder content (OBC) and 6% periwinkle shell ash (PSA) by weight of aggregates. However, the impact of the polyethylene/PSA blend on the HMA concrete's continued stability showed similar patterns independent of the soaking time. The polyethylene/PSA blend's rate of influence on the HMA concrete's swelling index increases as the filler content increases from 0% to 15%. Therefore, it can be concluded that submergence has a negative impact on the strength and volumetric properties of the HMA concrete but with the addition of a dual blend of PSA and polyethylene incorporated in the mix there was noticeable improvement in its stability and moisture resistance.