Nanocrystalline zirconia doped with 1mol%Eu3+ was prepared by co-precipitation method, Its structure was characterized with x-ray diffraction(XRD), the grain size of the nanocrystals was about 10nm obtained by XRD and Scherrer' equation. The luminescence of nanosized zirconia powders doped with Eu3+ ions was investigated under 394nm excitation, the emission of 5D0→7F2 transition peaked at 604nm. Furthermore, an enhanced emission at 604nm induced by ultraviolet irradiation was observed for the nanosized zirconia powders doped with Eu3+ ions.