Europium activated yttrium oxide phosphor powders (Y 2 O 3 :Eu 3+ ) were prepared from yttrium–europium precursors obtained by wet-chemical method. With this purpose in view, precursors were prepared using the reagent simultaneous addition SimAdd technique from yttrium–europium nitrate and chloride as rare-earth supplier and urea, ammonium oxalate, ammonium carbonate and oxalic acid as precipitating agents. Precursors, obtained under controlled concentration, temperature and pH conditions, were fired at 1200°C in order to generate Y 2 O 3 :Eu 3+ phosphor powders. Yttrium–europium precursors and Y 2 O 3 :Eu 3+ phosphor powders were investigated by FTIR, TGA–DTA, X-ray diffraction (XRD), scanning electronic microscopy (SEM) and photoluminescence spectroscopy (PL) in order to put in evidence the influence of the quality of yttrium–europium precursors obtained by wet-chemical method, using the SimAdd technique on the properties of Y 2 O 3 :Eu 3+ phosphor powders.