The　phase　transition　and　depolarization　phenomena　of　sodium　bismuth　titanate　[(Bi1/2Na1/2)TiO3,　BNT]　was　reviewed.　The　methods　determining　the　depolarization　temperature　were　represented.　Also,　the　depolarization　behaviors　of　traditional　BNT-based　systems　near　morphotropic　phase　boundary　(MPB)　were　summarized,　and　the　mechanisms　affecting　the　depolarization　temperature　of　BNT-based　systems　were　reviewed.　A　rule　for　the　novel　BNT-based　complex　systems　was　proposed　via　the　introduction　of　Bi-based　perovskite　Bi(B′B″)O3　as　second　end　member.　It　was　suggested　that　the　BNT-　Bi(B′B″)O3　systems　as-constituted　could　present　a　MPB　at　a　high　depolarization　temperature　by　utilizing　the　feature　of　Bi(B′B″)O3　with　a　low　tolerance　factor.