The　research　on　streaming　media　coding　and　transmission　technology　which　is　realtime　and　robust,　has　become　a　hotspot　in　current　information　technology.　As　a　method　of　solving　this　problem,　multiple　description　coding　(MDC)　is　concerned　widely,　due　to　satisfy　the　requirement　of　real-time　data　transmission　and　reduce　data　distortion.　This　paper　firstly　introduces　the　history　of　MDC　and　its　factors　for　evaluating　performance.　Then,　it　elaborates　the　research　and　progress　of　MDC,　including　the　ideas,　frames　and　characteristics　of　various　kinds　of　MDC　methods.　Finally,　it　discusses　the　difficult　problems　on　this　area.