The optical deflector includes a deflector, a vibration detector, a driving signal generator, a modulation timing signal generator, and a deflection detector. The deflector has a vibrational system having a movable body with a light deflecting member, and deflects light from a light source by the movable body. The vibration detector detects the vibration condition of the vibrational system of the deflector. The driving signal generator generates a driving signal for driving the vibrational system of the deflector. The modulation timing signal generator generates a modulation timing signal as the reference time for regulating the amount of light from the light source. The deflection detector detects the deflection condition of light deflected by the deflector. The driving signal generator generates the driving signal based on information of the vibration condition detected by the vibration detector, and the modulation timing signal generator generates the modulation timing signal based on information of the deflection condition detected by the deflection detector.