The　hybrid　machine　tool　is　a　challenging　topic　in　the　field　of　parallel　mechanisms.　A　novel　hybrid　machine　tool　with　a　2-DOF　parallel　mechanism　and　a　serial　orientation　is　investigated.　Based　on　some　assumptions,　the　elastic　restoring　force　and　elastic　vibration　model　of　the　mechanism　are　studied.　A　numerical　simulation　is　taken　for　the　example　of　an　end-milling　cutter　in　the　procedure　of　milling　a　plane.　The　influence　of　milling　parameters　on　the　vibration　characteristics　is　presented.　The　numerical　results　show　that　the　rotating　speed　has　an　important　effect　on　the　chaos　vibration　property　of　the　machine.　However,　the　depth　of　cutting　has　very　little　influence　on　the　chaos　characteristics　of　the　machine.