Polyvinylpyrrolidone (PVP)/[Y(NO3)3+Al(NO3)3] composite fiber was prepared by electrospinning. Yttrium aluminum garnet (YAG) nanofibers were fabricated by calcination of the relevant composite nanofibers. PVP/[Y(NO3)3+Al(NO3)3] composite nanofibers and YAG nanofibers were analyzed by using X-ray diffraction spectrometry, scanning electron microscopy, thermogravi- metric-differential thermal analysis and Fourier transform infrared spectrometry. The results show that PVP/[Y(NO3)3+Al(NO3)3] composite nanofiber is amorphous in structure, and pure phase YAG nanofibers are obtained by calcination of the PVP/[Y(NO3)3+Al(NO3)3] composite fibers at 900C for 10 h. The surface of as-prepared composite fibers is smooth, and the diameter of the composite fibers is about 175 nm. The diameter of the prepared YAG nanofibers is about 75 nm, and the length is greater than 100 μm. The mass of the sample remains constant when the temperature is above 550C, and the total mass loss percentage is 90.4%. The possible formation mechanism of the YAG nanofibers was preliminarily discussed.