This　article　proposes　a　tracking　algorithm　based　on　mean　shift　and　particle　filter　according　to　the　characteristics　of　moving　vehicles.　Firstly,　the　algorithms　establish　auto　target　motion　model　that　the　core　is　RGB　color　histogram.　Secondly,　using　the　Bhattacharyya　distance　measures　similarity　of　particle　region　and　the　target　model,　and　updating　the　weights　of　particles　according　to　the　similarity.　Lastly,　the　measure　improves　the　estimated　position　of　the　particle　by　using　mean　shift　algorithm,　which　makes　the　candidate　regions　of　these　particles　can　be　more　close　to　the　true　target　position.　Experimental　results　show　that　the　algorithm　has　good　real-time　performance　and　robustness,　and　can　achieve　stable　tracking　of　target　vehicle.