A light deflector comprises a first movable plate having a reflective surface, fixing portions, a pair of second movable plates located between the first movable plate and the fixing portions, a pair of first elastic members supporting the first movable plate so as to allow it to oscillate with respect to the second movable plates, a pair of second elastic members supporting the second movable plates so as to allow them to oscillate with respect to the fixing portions, and an actuator to oscillate the first movable plate. Oscillation axis of the first elastic members and oscillation axis of the second elastic members are located on the same axis. Stiffness of the second elastic members against oscillation is lower than stiffness of the first elastic members against oscillation.