In this work, TiO2-CeO2 heterojunction was fabricated via hydrothermal method and applied for photocatalytic degradation of sulfamerazine antibiotic from waste water under simulated sunlight irradiation. The prepared photocatalysts were characterized by XRD, SEM, EDX, DRS, and Mott-Schottky technique. According to the obtained results, CeO2 nanoparticles were successfully deposited on the TiO2 nanorods surface. Furthermore, the results of photocatalytic activity tests revealed that the photocatalytic efficiency was greatly elevated on TiO2-CeO2 heterojunction compared to the pure TiO2 and CeO2 samples, and the highest degradation percentage was achieved on the heterojunction with 20 mol.% CeO2 content. This could be ascribed to the efficient separation of charge carriers. Based on the Mott-Schottky calculations, and trapping experiments analysis, Z-scheme charge transfer was suggested to explain the enhanced photocatalytic activity.