In this study, we grew the Dy-doped Mg2SiO4 single crystals by the floating zone method to investigate the photoluminescence (PL) and thermally stimulated luminescence (TSL) properties. All the Dy-doped Mg2SiO4 showed the emission peaks at 480, 580, and 670 nm in PL and TSL spectra, and these peak wavelengths were typical for the 4f-4f transitions of Dy3+ ions. In the TSL glow curves, all the samples had glow peaks at 50, 200, 280, and 380°C. The TSL dose response function of the 1% Dy-doped Mg2SiO4 single crystals showed a good linearity across 1–10000 mGy.