Noble metals Ag and Pt were loaded on Na0.9Mg0.45Ti3.55O8 (NMTO) by chemical bath deposition method, which was synthesized firstly in our recent work. The scanning electron microscopy and transmission electron microscopy results show that Ag and Pt nanoparticles were distributed on the different surfaces of NMTO. NMTO loaded with Ag and Pt can efficiently enhance the separation of photogenerated electron-hole pairs, exhibiting much higher photodegradative ability for methylene blue and rhodamine B than the pure NMTO. The best weight concentrations of Ag and Pt are 9.00% and 3.70%, respectively. The electrostatic field is built in the Schottky barrier between NMTO and noble metals, leading to the energy band bending. Then, photogenerated electrons and holes are efficiently separated to enhance the photocatalytic activity.