A piezoelectric vibration device is provided that includes a piezoelectric transformer, a flexible board and a case. The flexible board includes an element-mounting terminal connected to an outer electrode of the piezoelectric transformer, and an external connection terminal connected to a wiring board. The case has a securing member that secures the case to the wiring board and a ceiling. When the piezoelectric vibration device is mounted on the wiring board, the securing member defines a space between the ceiling and the wiring board to accommodate the piezoelectric transformer and the flexible board. Moreover, the piezoelectric transformer is suspended to the ceiling of the case by a holding member. This configuration provides a piezoelectric vibration device with which degradation of characteristics due to causes such as displacement of the piezoelectric vibrator or fluctuations in the pressing force applied by lead terminals is minimized.