To provide a piezoelectric vibration device and a method for hermetic sealing thereof, capable of stable hermetic sealing complying with thin profiles.

A crystal vibrator 1 is composed of: a crystal substrate 3; and a first package base 2 and a second package base 4 consisting of a transparent material respectively joined to front and rear surfaces of the crystal substrate 3 through metal films 201, 301, 302, 401. Areas where the first and second package bases 2, 4 and the crystal substrate 3 are joined are not overlapped in a plan view.