A piezoelectric actuator for blood extraction pump in health monitoring system was developed. We devised the geometry of piezoelectric actuator with some slits, that allows the stretching and contracting deformation in in-plane direction to create large deflection in out-of-plane direction. The static behaviors under uniform electric field have been analyzed by finite element method. The computational results indicated that a bimorph actuator with cross slit under outside fixed condition is the most suitable for blood extraction pump. Abimorph actuator with cross slit l=4.0, w=0.5mm has been manufactured as an experiment. As a result, the developed actuator was proved to increase the deflection to 2.1 times at resonance frequency f=6460Hz.