Abstract: A survey of reprocessing of spent fuel elements over the world was made. The capacity of reprocessing does not fulfill the needs of nuclear power development at present and in the near future. The reprocessing remains its important position in the fuel cycle. The Purex process is still the main process not only for LWR fuel but also for FBR fuel. The recent R & D of reprocessing is focused on the improvement and the optimization of the process, especially on the so called salt free process including U4+,electro-reduction and oxidation, hydroxylamine, nitrous oxide and so forth. Processing of spent fuel with high burn-up should take special measure in order to avoid heavy radiolytic degradation of the solvent and the criticality of plutonium. Tritium must be controlled and confined in the definite area of the process in a small volume.