A driving method for a piezoelectric vibrator including a driving piezoelectric element and a detection piezoelectric element formed of the same material as a material of the driving piezoelectric element, for driving the piezoelectric vibrator by applying, to the driving piezoelectric element, an alternating
voltage having a frequency close to a
resonance frequency of the piezoelectric vibrator, the driving method including, in the case where it is detected based on variations in output detected from the detection piezoelectric element that at least one of variations in
mechanical resistance of the piezoelectric vibrator and variations in piezoelectric characteristic of a piezoelectric element have occurred, applying an alternating
voltage adjusted in accordance with the variations in
mechanical resistance of the piezoelectric vibrator and / or the variations in piezoelectric characteristic of the piezoelectric element, to thereby adjust an electrical input to the piezoelectric vibrator to suppress variations in
vibration amplitude of the piezoelectric vibrator.