To solve problems that fine adjustment is difficult in a method for directly cutting an electrode by using laser beams after sealing a small vibrator and there is no place where the cut electrode is discharged, so that the occurrence of contaminations such as wastes and dust is worried, and further these contaminations can be stuck to the surface of the vibrator, causing required characteristics of the vibrator to be deteriorated.

In the method for adjusting the frequency of a piezoelectric vibrator having a form that a piezoelectric plate on which an electrode is formed is held between a first substrate and a second substrate, an electrode metal is stuck to either one of electrodes formed at least on the front and rear sides of the first substrate and at least front and rear sides of the second substrate or the existing electrode metal is cut off to adjust the frequency of the piezoelectric vibrator.