To provide an ultrasonic hair treating device capable of evenly and surely permeating a treating agent over the entire hair bundle, shortening operation time and reducing power consumption.

The ultrasonic hair treating device 1 comprises a vibration part 5 provided with a vibrator 7 for generating ultrasonic vibrations and a receiving part 6 facing the vibration part 5, clamps the hair bundle H by the vibration part 5 and the receiving part 6 and transfers the ultrasonic vibrations of the vibrator 7 to the hair. The vibrator 7 in a rectangular plate shape is provided as the vibrator 7. One surface in the thickness direction of the vibrator 7 is turned to a vibration surface 7a. The vibration surface 7a is vibrated so that resonance points A are positioned at multiple points in grid point shape.