An electric stimulator for alpha-wave derivation is characterized in that frequency selected from a range of 1 Hz to 50 Hz, preferably, 7 Hz to 14 Hz, and an output voltage are applied to auricle of a patient's ears to derive alpha-waves, and that cycle and intensity of stimulation are varied depending upon body temperature and blood sugar. Prompt reaction may be obtained by directly applying the voltage to the ears, and the reaction may continue when stimulation is extended. In addition, it is suitable to treat various diseases having common cause due to stress or arousal reaction in the human body.