Featured　Application　The　proposed　method　in　this　paper　can　be　applied　to　the　field　of　precision　manufacturing　of　the　end　milling　process.　The　semi-conical　shell　workpiece　is　a　special　kind　of　thin-wall　part　that　is　commonly　used　in　aerospace　and　mold　industries.　Due　to　the　special　stiffness　distribution　and　weak　rigidity　for　the　area　with　a　large　radius,　the　machining　quality　of　the　semi-conical　shell　is　sensitive　to　both　cutting　force　and　vibration.　Conventionally,　constant　conservative　machining　parameters　are　chosen　to　ensure　the　workpiece　deformation　and　surface　quality,　which　will　reduce　the　machining　efficiency.　Based　on　the　cutting　force　and　vibration　response　simulation　of　the　whole　milling　process.　A　feed　rate　variation　strategy　is　proposed　for　the　ball　head　end　milling　process　of　the　semi-conical　shell　workpiece.　The　cutting　force,　dynamic　performance　and　stability　prediction　are　obtained　considering　the　shape　and　boundary　conditions　of　the　workpiece　and　the　contour　tool　path　of　the　milling　process.　Variable　feed　rate　is　used　in　the　milling　simulation　to　find　the　harmony　between　machining　quality　and　efficiency.　User-defined　vibration　amplitude　and　another　user-defined　cutting　force　threshold　are　used　to　find　the　optimal　feed　rate　for　each　simulation　segment.　Both　continuous　and　discrete　feed　rate　variation　strategies　are　proposed,　and　the　improved　discrete　feed　rate　variation　is　applied　in　the　milling　experiment.　About　25%　of　the　consumed　time　is　saved　with　almost　the　same　machining　quality　by　the　experimental　results.