Abstract: A stable LaPO₄:Eu³⁺ red phosphor was prepared by hydrothermal method. The influences of the concentration of Eu³⁺ and calcination temperature on the luminescent properties were studied. The crystal structure, particle size and morphology were characterized by X-Ray Powder Diffraction (XRD) and Scanning Electron Microscope (SEM) techniques. The luminescent properties of phosphor were measured by emission spectra, excitation spectra and decay curve. The results indicate that the precursors are the LaPO₄·0.5H₂O crystals of hexagonal without heat-treatment, the as-prepared samples are LaPO₄:Eu³⁺ crystals of monoclinic phase annealing at 900 ℃, the length of crystal is about 500 nm, the width is about 300 nm. The maximum emission and excitation wavelength are at 592 nm and 393 nm, respectively. The emission peaks at 592 nm and 612 nm are corresponding to ⁵D₀→⁷F₁ and ⁵D₀→⁷F₂ transition of Eu³⁺ ions in emission spectrum. The fluorescence lifetime of LaPO₄:Eu³⁺ phosphor is 3.32 ms.