Restraining　the　noise,　meanwhile,　improving　the　dynamic　characteristics　of　the　driving　power　of　piezoelectric　pump　effectively　are　the　final　purposes　of　doing　research　on　the　reciprocating　and　flexural　vibration　of　the　piezoelectric　vibrator.　However,　among　many　papers　regarding　piezoelectric　pump,　there　are　very　few　papers　about　the　research　on　the　noise　of　piezoelectric　pump.　This　is　far　less　than　the　research　on　the　application　of　the　piezoelectric　pump　in　other　fields.　In　this　paper,　the　research　on　the　flexural　vibration　deformation　and　vibration　radiation　noise　of　the　piezoelectric　vibrator　are　carried　out.　Firstly,　the　vibration　equations　of　the　piezoelectric　vibrator　are　built　and　flexural　vibration　deformation　function　is　deduced.　Then,　the　simplified　vibration　model　of　the　piezoelectric　vibrator　is　introduced　by　using　vibration　theories　of　micro-area　piston.　Furthermore,　theoretical　calculation　equations　of　sound　pressure　in　close　noise　field　and　noise　contribution　equation　of　fluid　in　pump　are　deduced.　Finally,　a　comparison　is　made　between　the　theoretical　calculation　value　and　experimental　value,　and　the　contribution　quantities　of　the　piezoelectric　vibrator　and　fluid　in　pump　are　obtained　respectively　under　different　frequencies.　The　consequence　approves　that　the　theory　introduced　by　this　research　is　true.　©　2006　IEEE.