In an optical deflector including a mirror, a support frame surrounding the mirror, at least one torsion bar arranged along an axis of the mirror having an end coupled to an outer circumference of the mirror, a pair of piezoelectric actuators arranged between the support frame and the torsion bar, and a piezoelectric sensor inserted between the torsion bar and one of the piezoelectric actuators, the piezoelectric sensor includes at least one piezoelectric sensor element having a width being smaller than two-fifths of a width of the one of the piezoelectric actuators and being arranged at a wide portion within two-fifths of the width from an inner end of the one of the piezoelectric actuators.