Pr-doped Ky(3)F(10) (Pr:KYF) single crystals were grown by the micro-pulling-down (mu-PD) method. The crystals were transparent with a slightly greenish color, 2.5-3.0 mm in diameter and 35-45 mm in length. Neither visible inclusions nor cracks were observed. Photoluminescence spectra and decay kinetics of Pr:KYF were measured. Emission due to Pr3+ 5d-4f transition, peaking around 260 nm and of the decay time of 24 ns was observed. The short decay time suggests such a Pr-doped material for a scintillator application. To our knowledge, this is the first report of the Pr3+ 5d-4f luminescence transition accomplished in a fluoride host. (c) 2005 Elsevier B.V. All rights reserved.