Y2O3 luminescent nanoparticles were synthesized via new protocol of sol–gel method combined with a furnace firing in air, using metal salt as precursor and an epoxide for hydrolysis. Effects of rare earth (Tb3+) doping on structural and luminescence properties of the produced nanophosphors have been investigated. The obtained nanopowders were characterized by various techniques such as thermogravimetric analyser (TGA), differential thermal analyser (DTA), transmission electron microscopy (TEM), X-ray diffraction (XRD), photoluminescence spectroscopy (PL) and photoluminescence excitation (PLE). After thermal treatment at different temperatures in air, the powder with an average particle size of 50 nm presents a green luminescence band in the visible range (544 nm). The intensity of the obtained PL band increases with of thermal treatment temperature and the PLE spectra present an intensive band in UV-range corresponding to Y2O3 band-gap. Different origins of this evolution will be discussed.