Several countries reprocess their nuclear spent fuel using the Purex process to recover U and Pu as MOX fuel. The high level radioactive waste (HLW) produced during this reprocessing is a complex mixture containing both radioactive (fission products, minor actinides) and non-radioactive elements. Since HLW shows high rate heat release and contains some long half-life and biologically toxic radionuclide, its treatment and disposal technology is complex, difficult and high cost. HLW treatment and disposal become a worldwide challenge and research focus. In order to minimize the potential long-term impact of HLW, studies on enhanced chemical separation processes of long-lived radionuclides are in progress. Two options are then envisaged for these separated radionuclides: (a) transmutation into short-lived or non-radioactive elements, (b) immobilization in highly durable ceramic matrix instead of borosilicate glass. In this paper, we briefly review the composition, structure, processing and product properties of some ceramic candidates for inert matrix fuels (IMF) and the immobilization of high level radioactive waste.