Eu2+, Dy3+ co-doped strontium aluminate (SrA1(2)O(4)) phosphor nanometer powders with high brightness and long afterglow were prepared by heating the precursor gel (resulted from sol-gel method) at 900 degreesC and a reductive atmosphere of active carbon. The average particle size of the SrA1(2)O(4):Eu, Dy phosphor powders was 59 +/- 7 nm and its optical properties have been studied systematically. The broad band UV excited luminescence of the SrA1(2)O(4):Eu, Dy was observed at lambda(max) = 506 nm due to transitions from the 4f(6)5d(1) to the 47 configuration of the EU2+ ion. The results indicated that the main peaks in the emission and excitation spectrum shifted to the short wavelength compared with phosphor obtained by the solid-state reaction synthesis method. The decay speed of the afterglow for nanometer phosphors was faster than that obtained by the solid-state reaction method. (C) 2004 Elsevier B.V. All rights reserved.