In this paper, we describe a novel nanocomposite structure consisting of CsPbI3 crystals growing on carbon nanofibers by electrospinning and following thermal treatment. Detailed characterization results reveal that these CsPbI3 crystals are single-crystalline with high thermal stability. The resultant composite nanofibers show wide bandgap of 2.71 eV and narrow photoluminescence full-width-at-half maximum (FWHM) of 29 nm, exhibiting fluorescence quenching phenomenon after thermal treatment. These composite nanofibers with a welldefined morphology offers new opportunities for high-performance optoelectronic devices.