To　study　the　effect　of　the　contact　angle　and　helix　angle　on　slide-roll　ratio　at　the　ball　contact　points　under　the　accelerated　motion　state　of　ball　screw　mechanism　(BSM),　the　curve　theory　in　differential　geometry　and　the　homogeneous　transformation　matrix　are　used　to　establish　the　acceleration　kinematics　model　of　BSM.　The　model　can　be　used　to　describe　the　accelerated　motion　relationships　among　the　screw,　balls　and　nut,　calculate　the　acceleration　of　relative　motion　at　the　contact　points　between　the　balls　and　raceways,　and　analyze　five　accelerated　motion　rules　between　the　balls　and　raceways.　It　also　conducts　a　simulation　analysis　of　the　slide-roll　ratio　relationship　between　the　accelerations　at　the　ball　center　and　the　contact　point　of　ball　under　different　contact　angles　and　helix　angles.　As　shown　by　the　analysis,　with　the　increase　in　the　BSM＇s　contact　angle,　the　slide-roll　ratio　at　the　contact　points　decreases,　and　the　contact　angle　has　a　relatively　significant　effect　on　the　slide-roll　ratio.　However,　with　the　decrease　in　the　BSM＇s　helix　angle,　the　slide-roll　ratio　at　the　contact　points　decreases,　and　the　helix　angle　has　a　relatively　insignificant　effect　on　the　slide-roll　ratio.　By　measuring　the　accelerations　of　both　the　screw　and　nut　under　the　accelerated　motion　state,　it　also　verifies　the　existence　of　the　slide-roll　mixed　motion　at　the　ball　contact　point　A　between　the　ball　and　the　screw　raceway　and　pure　rolling　at　the　ball　contact　point　B　between　the　ball　and　the　nut　raceway　during　the　accelerated　motion.　©　2017,　Editorial　Department　of　Journal　of　Southeast　University.　All　right　reserved.