Specially　designed　SmCo5/Co　magnetic　nanocomposites　have　been　fabricated　by　a　＂bottom　up＂　process.　SmCo5　nanochips　were　first　prepared　by　solution-phase　chemical　synthesis　combined　with　reductive　annealing　and　then　coated　by　chemical　deposition　of　Co　nanorods.　Both　the　SmCo5　nanochips　and　Co　nanorods　are　anisotropic　and　could　be　simultaneously　aligned　under　the　external　magnetic　field.　Magnetic　measurements　applied　on　these　＂bi-anisotropic＂　SmCo5/Co　composites　show　high　magnetic　performance　with　the　Co　phase　content　in　a　wide　range　from　10　to　80　wt　%.　For　the　first　time　ever,　the　applicable　exchange-coupled　nanocomposites　with　a　rareearth　content　lower　than　7　wt　%　was　realized,　which　exhibits　the　coercivity　close　to　10　kOe　and　remanence　31%　larger　than　that　of　single　phase　SmCo5.　3-D　micromagnetic　simulations　were　performed　to　reveal　that　the　reversal　mechanism　in　the　Co　phase　was　transferred　from　the　incoherent　mode　to　the　coherent　mode　under　a　tip　interface　exchange-coupling　with　a　SmCo5　surface.