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Titanium dioxide (TiO2) has been employed to degrade hazardous materials since its photocatalytic ability was discovered. In recent years, attempts have been made to apply TiO2onto road surfaces to degrade the harmful compounds (such as NO and NO2) from vehicle emissions. As a photocatalyst, the NOXdegradation efficiency of TiO2largely depends on its surface area exposed to sunlight. However, the effective coating methods to enlarge the contact area between the coated TiO2and sunlight have not been well studied, especially for asphalt pavements. To fill this gap, this study aims to investigate the photocatalytic performance of three TiO2coating methods for asphalt pavements, including the conventional water-solution-based TiO2(WT) coating, and the innovative glass-bead-based TiO2(GT) coating and porous TiO2(PT) coating. A custom-designed environmental test setup was used to determine the NOXdegradation efficiency of the specimens with TiO2coating, and the durabilities of the coating materials were characterized by measuring their NOx degradation efficiency subjected to different numbers of lab-simulated tire abrasion. It was found that the PT and GT methods provided not only better NO degradation efficiency but also improved durability compared to the conventional WT method.