PURPOSE: To obtain the vibrator for a vacuum sensor which is small in equivalent serial resistance, small-sized, strong in the impact and excellent in the reliability by arranging the exciting electrode with a different polarity at both edge parts of the vibrator.

CONSTITUTION: For a piezoelectric vibrator 1, the supporting part 3 is fixed by adhesives 4, etc., on a supporting base 2 composed of a ceramics material, etc. The exciting electrode is arranged on the four surfaces of respective arms, the number of electrodes is two pieces each on respective surfaces and arranged so that the adjoining electrode can be the different electrode. Namely, electrodes 5, 6, 7, 8, 9 and 10 of one side arm are connected so that electrodes 5, 7 and 9 and electrodes 6, 8 and 10 can be the same electrodes, altogether in the same way, electrodes 11, 12, 13, 14, 15 and 16 of other arm also are connected so that electrodes 11, 13 and 15 and electrodes 12, 14 and 16 can be the same electrodes and these polarities are arranges so that they can be opposite. Thus, both edge fixing bending mode secondary higher harmonic vibration can be easily extracted, thereby the equivalent serial resistance can be made smaller.