The invention discloses a rare earth permanent magnet produced by applying abundant rare earth cerium (Ce) and a preparation method of the rare earth permanent magnet produced by applying abundant rare earth Ce. Based on a double-alloy process, main phase alloy formula uses Ce to partly replace neodymium (Nd), an optimized composition design enables a main alloy to form Ce2Fe14B phase and Nd2Fe14B phase to a greatest extent, and therefore high intrinsic magnetic property is guaranteed. A brand new crystal boundary phase is prepared by a crystal boundary reconstitution technology, and high integral magnetic property and corrosion resistant property are guaranteed, and meanwhile a nanometer powder crystal modification method is supplemented, a micro organization structure of a magnet is optimized, crystal boundary distribution is improved, and the magnetic property and the corrosion resistant property are further improved. By applying abundant rare earth cerium, cost is effectively reduced, and meanwhile balance between production and marketing is promoted. Praseodymium (Pr), Nd, and the like are chosen to form a hard magnetic shell layer of a main phase boundary in a composition design of crystal phase auxiliary alloy at the same time, compared high price heavy rare earth elements of dysprosium (Dy) and terbium (Tb) with the elements, and cost control can be further achieved.