In this study, photo and thermo-luminescent properties of Nano crystalline Mg2SiO4:Dy3+ prepared by a hydrothermal method were studied and compared to those of nanoparticles prepared by combustion method. The synthesized sample was characterized by X-ray diffraction, transmission electron microscopy, scanning electron microscopy and photoluminescence spectroscopy. The effect of Dy concentration on photo and thermoluminescent intensities was studied. The X-ray diffraction (XRD) patterns of the samples revealed that forsterite was formed as a major phase for all the samples. The crystallite size was found to be in the range of 20-50 nm. The thermo luminescent glow curve indicated that the hydrothermal sample was more efficient than the combustion sample. Two prominent TL bands located at 200 nm and 320 nm were recorded. The prepared nanoparticles exhibited a roughly linear dose response to absorbed dose of 1000 Gy received from 60Co gamma source, suggesting that nanomaterial could be a good candidate for high dose dosimetry. (C) 2016 Elsevier Ltd. All rights reserved.