Novel structures of Y3Al5O12: Eu3+ (denoted as YAG: Eu3+ for short) nanobelts were fabricated by calcination of the electrospun PVP/[Y(NO3)(3)+Eu(NO3)(3)+Al(NO3)(3)] composite nanobelts. X-ray powder diffraction (XRD) analysis showed that YAG: Eu3+ nanobelts were cubic in structure with space group I(a)3d. Fourier transform infrared spectroscopy (FTIR) analysis manifested that pure YAG: Eu3+ nanobelts were formed at 900 degrees C. Scanning electron microscope (SEM) analysis indicated that the YAG: Eu3+ nanobelts have coarse surface. The width and thickness of YAG: Eu3+ nanobelts were ca. 3.25 mu m and ca. 220 nm, respectively. Fluorescence spectra analysis revealed that YAG: Eu3+ nanobelts emitted the main strong emission centering at 592 nm under the ultraviolet excitation of 235 nm, which was attributed to D-5(0)-> F-7(1) of Eu3+, and the optimum doping molar concentration of Eu3+ ions was 5%. CIE analysis demonstrated that the emitting colors of YAG: Eu3+ nanobelts could be tuned by adjusting doping concentration of Eu3+. The possible formation mechanism of YAG: Eu3+ nanobelts was also proposed.