Undoped and Dy3+-doped PbWO4 single crystals were grown in the same condition by modified Bridgman method. Optical transmittance, X-ray excited luminescence, excitation and emission under UV light, thermoluminescence glow curves and X-ray pulsed excited decays were investigated on Dy3+ TWO for the first time. Dy3+-doping has a positive effect similar to that of rare-earth ions La3+ and Gd3+, such as improvement of transmittance in the wavelength region of scintillation emission (350-450 nm), compensation of trapping centers that is reflected in the thermoluminescence characteristics and suppression of slow decay component in luminescence kinetics. Analysis of luminescence spectra indicates that energy transfer could take place from the PbWO4 host to the Dy3+ ions, followed by characteristic emission line assigned to transition from 4F(9/2) of Dy3+ ion to lower lying states on basis of the energy level scheme. A tentative concept of energy transfer mechanism is proposed in this paper. (C) 2002 Elsevier Science B.V. All rights reserved.