A　file　format　for　storage　of　scalable　video　is　proposed.　A　generic　model　is　presented　to　enable　a　codec　independent　description　of　scalable　video　stream.　The　relationships,　especially　the　dependencies,　among　sub-streams　in　a　scalable　video　stream　are　specified　sufficiently　and　effectively　in　the　proposed　model.　Complying　with　the　presented　scalable　video　stream　model,　the　file　format　for　scalable　video　is　proposed　based　on　ISO　Base　Media　File　Format,　which　is　simple　and　flexible　enough　to　address　the　demands　of　scalable　video　application　as　well　as　the　non-scalable　ones.