The monodisperse popcorn-like CeO2 nanostructures with crude surface covered by wrinkles completely and a diameter of 150-300 nm have been successfully synthesized by a facile hydrothermal technology. XRD, SEM, XPS, Raman scattering and M-H curve were employed to characterize the samples. The results showed that the popcorn-like CeO2 nanostructures have a cubic fluorite structure and there are Ce3+ ions and oxygen vacancies existing in their surface. The magnetic measurement indicated that the popcorn-like CeO2 nanostructures possess excellent ferromagnetism at room temperature, which can be attributed to the influences of the morphology of the particles, Ce3+ ions and oxygen vacancies.