In this paper, submicron-sized spherical Sr2MgSi2O7:Eu2+, Dy3+ phosphors were prepared via sol–gel methods and hydrothermal coprecipitation methods. The effect of different preparation methods on the luminescence properties and microstructures were studied using X-ray diffraction, fluorescence spectra analysis, decay curves, scanning electron microscopy, transmission electron microscopy and laser particle size analysis. Results indicate that the average size of the phosphors via sol–gel methods and hydrothermal coprecipitation methods were 0.711 and 0.389 µm, respectively, and their luminous intensities increased by 20 and 80% as compared to phosphors of the solid state methods, respectively.