Abstract: To investigate the effect of atomically dispersed Ag-loaded TiO₂ mesoporous nanobelts on photocatalytic oxidation activity, Ag clusters-TiO₂ nanobelts (NBs) were prepared through a facile process, including a mild reduction of Ag⁺ on the surface of TiO₂ mesoporous nanobelts and a moderate heat treatment, which formed atomically dispersed Ag with strong metal-substrate interaction (MSI). The microstructure, light absorption, carrier separation and photocatalytic oxidation performance of prepared materials were investigated by XRD, STEM, UV-vis, PL, EXAFS and other techniques. Results show that Ag clusters-TiO₂ NBs exhibit an excellent photocatalytic oxidation activity for gaseous pollutants under visible light irradiation. At low Ag loading (w=0.1%), the photodegradation efficiency of NO reaches 56.04%, and the removal rate of formaldehyde is 95.20%, which are 2.29 times and 1.22 times higher than that of Ag NPs-TiO₂ NBs counterpart, respectively. TiO₂ mesoporous nanobelts provide abundant anchor sites allowing Ag to disperse atomically, resulting in increased number of catalytically active sites. The strong interaction between Ag cluster and TiO₂ and the reversible oxidation state of Ag cluster favor the activation of oxygen and the effective utilization of photogenerated carriers.