Europium- and terbium-doped zinc aluminate oxide nanocrystals with a spinel structure were successfully prepared by a combustion method, using urea as fuel. The samples thus obtained were characterized by X-ray diffraction, scanning electron microscopy and luminescence spectroscopy. X-ray diffraction results confirmed the formation of ZnAl2O4 spinel phase and a minor amount of ZnO. Our SEM results revealed agglomerates in the shape of irregular plates composed of nanoparticles with dispersed points of second phase in the surface. Powders containing Eu3+ and Tb3+ ions displayed red and green photoluminescence, respectively.