To provide an energy confinement piezoelectric vibrator that keeps an impedance characteristic without spurious radiation and to provide its polarization method.

The energy confinement piezoelectric vibrator is configured by forming a plurality of driving or detection electrodes to a major side of a piezoelectric substrate 2. Rectangular electrodes 1a and 1b whose corner angles are extended to be acute angles are places on and under only a vibration region surrounded by the electrodes where energy confinement vibration is caused and the vibrator is polarized in the perpendicular direction of the piezoelectric substrate 2.