A sensing device is configured that a first piezoelectric vibrator and a second piezoelectric vibrator, changing over a connection to an oscillation circuit, have the oscillation circuit in common, that an impedance of a conductive path including a first one-surface-side electrode constituting the first piezoelectric vibrator from the oscillation circuit and an impedance of a conductive path including a second one-surface-side electrode constituting the second piezoelectric vibrator from the oscillation circuit are uniform with each other, and that an impedance of a conductive path including a first other-surface-side electrode constituting the first piezoelectric vibrator from the oscillation circuit and an impedance of a conductive path including a second other-surface-side electrode constituting the second piezoelectric vibrator from the oscillation circuit are uniform with each other.