The　article　mainly　focused　on　the　design　of　the　control　system　based　on　C8051F330　to　control　the　speed　of　an　axial　flow　blood　pump.　On　one　hand　the　terminal　voltage　comparison　was　used　to　recognize　the　rotor　position;　on　the　other　hand　in　order　to　capture　the　edge　of　position　signal,　the　external　interrupt0　of　the　MCU　was　used　that　can　reduce　the　interference　that　came　from　the　axial　flow　blood　pump.　The　results　of　the　experiment　showed　that　the　phase　differences　of　the　position　signals　were　60　electrical　degrees,　which　coincide　with　the　classical　theory,　Back-EMF　crossing-zero　sensing　method.　And　the　periodic　time　of　the　position　signal　was　about　6.7ms,　the　corresponding　speed　was　8,955RPM　that　nearly　equal　to　the　reference　speed　9,000RPM.　Therefore　the　result　demonstrated　that　by　utilizing　this　control　system　the　blood　pump　could　be　driven　steplessly　without　bounce　or　losing　step.　The　control　system　had　the　following　advantages:　small　volume,　simple　structure,　high　reliability,　favorable　speed　performance,　and　low　power　consumption.　Hence,　this　control　system　was　qualified　for　the　axial　flow　blood　pump.