Tb-ZnO/reduced graphene oxide (Tb-ZnO/RGO) nanocomposites were prepared by a simple one-step sol-vothermal method. The samples were characterized by XRD, SEM, XPS, BET, FT-IR, and Raman spectroscopy, and their photocatalytic activities toward different pollutants (RhB, MO, PR, and MB) degradation were eval-uated. Tb-ZnO/RGO nanocomposite shows enhanced photocatalytic activity with high kinetic constants (0.04 min-1) and good stability. Enhanced charge separation and migration have been analyzed using UV-Vis ab-sorption spectra, PL spectra, and EIS analysis. Improved photocatalytic activity can be ascribed to the smaller band gap, larger specific surface area (28.3478 m2/g) and more effective separation and transport of photo-generated carriers by Tb3+ and RGO. All the results show that the nanocomposite catalyst has a good application prospect in the degradation of pollutants.