In　order　to　meet　the　rapid　development　need　of　embedded　video　surveillance,　a　method　of　moving　object　detecting　and　tracking　based　on　MPEG-4　video　is　proposed　in　this　paper.　In　the　method,　moving　objects　are　detected　by　threshold　segmenting　and　morphological　filtering　of　motion　vector　in　MPEG-4　encoding.　The　implementation　on　ADSP-BF533　and　its　results　are　presented.　The　results　show　that　the　method　can　detect　moving　object　correctly　and　be　applied　to　practical　surveillance　system.