Indonesia is a tropical country with high rainfall, which necessitates pavement with higher void content and good drainage conditions. The quality of road pavement depends on the materials used. One type of asphalt mixture with high void content and permeability but low stability is porous asphalt. This is due to the composition of porous asphalt, which consists predominantly of coarse aggregates compared to fine aggregates. This study utilizes waste tires, Low-Density Polyethylene (LDPE), gilsonite, and 60/70 penetration asphalt as binders, referred to as modified asphalt, in porous asphalt mixtures. The objective of this study is to determine the Optimum Asphalt Content (OAC) using waste tires, LDPE, gilsonite, and 60/70 penetration asphalt as binders in porous asphalt mixtures and to compare it with the OAC of conventional asphalt. The method used in this research is based on the Australian Asphalt Pavement Association (AAPA) (2004) method, employing open-graded porous asphalt with a maximum aggregate size of 14 mm. According to AAPA (2004), OAC determination requires three parameters: Cantabro Loss (CL), Asphalt Flow Down (AFD), and Voids in Mix (VIM). The study began with testing the physical properties of aggregates and asphalt, both conventional and modified. After testing the physical properties, the next step was determining the optimum asphalt content. The OAC obtained for porous asphalt mixtures using modified asphalt as a binder was 5.3%, while the OAC for conventional asphalt was 5.75%, serving as a comparison.