The　paper　calculates　the　grey　incidence　degree　of　the　Research　and　Development　investment　and　Economic　Development　in　some　countries　on　the　basis　of　the　grey　incidence　theory　in　the　main　three　performance　sectors.　The　results　demonstrate　that　the　investment　of　science　and　technology　talents　is　more　important　than　R&D　expenditure　in　promoting　the　development　of　economy.　R&D　expenditure　gets　higher　degree　of　grey　incidence　in　government　performance　sector　than　the　researchers　in　China.　The　researcher　input　in　business　enterprise　sector　should　be　improved.　To　be　supported　by　more　R&D　funds　is　necessary　for　the　high　education　sector.　©　2010　IEEE.