In　spite　of　the　fact　that　rare　earth　oxides　can　improve　the　sealing　properties　of　glass-ceramics,　the　electrical　stability　of　these　glass-ceramics　under　Solid　Oxide　Fuel　Cell　(SOFC)　operational　conditions　still　remains　ambiguous.　In　this　work,　the　electrical　stability　of　glass-ceramics　doped　with　La2O3　or　CeO2　under　SOFC　operational　conditions　has　been　systematically　investigated.　The　glass-ceramic-material　with　La2O3　dopant　exhibits　good　electrical　stability　under　SOFC　operational　conditions;　whereas,　a　decrease　in　the　conductivity　of　the　CeO2-containing　glass-ceramic　material　can　be　related　to　the　formation　of　a　conductive　phase,　i.e.,　CeO2.　In　particular,　the　relationship　between　the　phase　evolution　and　the　change　in　conductivity　of　glass-ceramics　has　been　clearly　demonstrated.　Moreover,　the　sealing　glass-ceramics　show　good　chemical　compatibility　with　8　mol%　yttria-stabilized　zirconia　(8YSZ)　electrolyte,　after　being　held　at　750　degrees　C　for　1000　hours.　The　reported　results　support　the　suitability　of　La2O3-containing　glass-ceramic　as　a　sealing　material　for　SOFC　applications.