Gd ₂O ₂S:Dy ³⁺  phosphors were synthesized by a homogeneous precipitation method from Gd ₂O ₃, Dy ₂O ₃, H ₂SO ₄ and Urea starting materials. The characterizations of Gd ₂O ₂S:Dy ³⁺  phosphors were investigated by means of XRD, FE-SEM and PL spectra. XRD analysis shows that the precursor can be transformed into pure Gd ₂O ₂S powder by calcining at 900 ℃ for 1 h in hydrogen. FE-SEM observation shows that the Gd ₂O ₂S powder particles are quasi-spherical in shape, with a mean particle size of about 300~500 nm. Photoluminescence (PL) spectroscopy reveals that the main and second emission peaks are located at 579 nm and 488 nm under 270 nm UV light excitation, which corresponds to the  ⁴ F _9/2→ ⁶H _13/2 and the ⁴F _9/2→ ⁶H _15/2 transitions of Dy ³⁺ ions, and both transitions of Dy ³⁺ ions have a single exponential decay behavior. The quenching concentration of Dy ³⁺ ions is 1 %. The CIE coordinate and the color temperature of (Gd _0.99,Dy _0.01) ₂ O ₂S phosphor are (0.308, 0.379, 0.313）and 6 464 K respectively.