The preparation of Y2O3:Ln(3+) (Ln = Eu, Er; nominal 1-0.1 mol % doping) by the preformed sol method is reported. The comparison of the emission spectra with more concentrated samples prepared by flame spray pyrolysis and conventional spray pyrolysis shows that emission from D-5(1) is quenched in the latter samples, and C-3i site emission is relatively weaker, when compared to C-2 site emission. Experimental data are provided to dispute the recent reassignments of the energy levels of Eu3+ situated at C-3i sites in Y2O3. The comparison of the emission spectrum of micrometer-scale Y2O3:Er3+ with that previously reported for nanoscale material shows a significant enhancement of hot bands in the latter. The enhanced population of H-2(11/2) leads to rather different behavior in the energy transfer phenomena of the nanoscale material.