Tb3+-doped CePO4 flower-like clusters were hydrothermally synthesized without using any template or surfactant by varying the reactant Tb3+ cation concentration. It was observed that the flower-like clusters were composed by nanowires with a diameter of about 80～90 nm and lengths up to 1 μm. The structures, morphologies, sizes and luminescence properties of the products were studied by X-ray powder diffraction (XRD), field-emission scanning electronic microscopy (FE-SEM), and luminescence spectra. With the reactant Ce3+/Tb3+ molar ratio of 0.850∶0.150, the uniform flower-like clusters were actually composed of a self-assembly of the oriented nanowires through an Tb3+-induced in the excessive PO3-4. It was found that the reactant Ce3+/Tb3+ molar ratio and phosphoric acid played key roles in the morphology control of the product. A possible formation mechanism for the flower-like morphology was also proposed. The luminescence properties of CePO4∶Tb flower-like cluster were performed, indicating that the strongest emission intensity was reached with 0.850∶0.150 molar ratios of Ce3+/Tb3+.