In an electrical stimulation device and an electrical stimulation method thereof, electrical stimulation can be adjusted more in real time, and stability and safety of the electrical stimulation can be more improved. An electrical stimulation device includes an electrode an electrical signal supply section, a skin impedance detection section, and an electrical signal controller. The electrical signal supply section supplies an electrical signal for generating the electrical stimulation to the electrode. During the supply of the electrical signal, the electrical signal controller acquires information associated with skin impedance through the skin impedance detection section in a cycle shorter than a supply period of the electrical signal, and adjusts the electrical signal to be supplied to the electrode in the next cycle based on the acquired information associated with skin impedance.
