To provide a treatment apparatus and a treatment method for enhancing moisture retaining property of the whole skin (especially the face) and/or hair.

The treatment apparatus is composed as follows: (1) a chemical liquid tank 3 is provided in a water tank 1 and the bottom of the water tank 1 is provided with an ultrasonic wave generator 7; (2) ultrasonic waves (indicated by an arrow (a)) emitted from the ultrasonic wave generator reaches the surface 4 of the chemical liquid, and ultrafine mist (nanomist 8) of the chemical liquid is generated; and (3) the nanomist 8 is sent by air from a blower 9 and sprayed from a mist nozzle 13 to form a mist jet 14. The treatment method includes γ-PGA (gamma-polyglutamic acid) as the chemical liquid. The apparatus increases permeation of the chemical liquid to the skin or hair, and the moisture retentivity is improved.