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Europium-doped titania nanocrystals were prepared by sol-gel technique and were characterized by X-ray Diffraction (XRD) and Photoluminescence (PL) spectra. XRD results showed pure anatase phase structure of titania, which indicated Eu3+ ions were possibly located in the region near the surface of titania nanocrystals grain. At room temperature, PL spectra were measured; luminescence of the host of titania came from the free excitons, band excitons and defect energy levels respectively under the excitation of 260nm. When these samples were excited under Uv-vis light of 380nm, 395nm, 415nm and 468nm, the spectra showed a series of PL signals which corresponded to characteristic emission of Eu3+ions and excitation efficiency was highest at 468nm, while it was hardly 0 at 380nm, that is to say, 468nm was most sensitive excitation line, while in general, it is at 395nm, therefore, the excitation source was extended from ultraviolet to visible light, which was very beneficial to luminescence. These emission peaks corresponded to the transitions of 5D0 -> 7FJ (J = 0-4) of Eu3+ ions respectively, and pure red luminescence at 616nm arising from the transition of 5D0 -> 7F2 was strongest. The excitation spectra exhibited efficient excitation absorption of the host band gap was quite weak.
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