The purpose of this study is to explore the effects and safety of transcutaneous electrical nerve stimulation (TENS) at home for patients diagnosed with insomnia on the improvement of insomnia and nervous stability.

Inclusion Criteria:

• Men and women between the ages of 19 and under 65
• Those who meet the criteria for the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) for Insomnia
• Those with a score of 8 or higher based on the Korean version Insomnia severity index (ISI-K)
• A person whose sleeping environment and habits are regular, usually between 9:00 p.m. and 1:00 a.m., go to bed, lie down for 7 to 10 hours, and wake up between 5 and 10 a.m.
• In the case of patients who regularly take drugs for improving insomnia at least once a week, those who agree to discontinue taking the prohibited drugs in this study for a total of 5 weeks, 1 week to remove the drug effect after screening and 4 weeks for the clinical study period
• Persons who do not have a reason to prohibit the use of electrotherapy that can significantly affect biomarkers in relation to this study
• A person who voluntarily decides to participate and agrees in writing to abide by the precautions after hearing and understanding a sufficient explanation about this clinical trial

Exclusion Criteria:

• Those who have been diagnosed with sleep arousal disorders other than insomnia (hypersomnia disorder, narcolepsy, breathing-related sleep disorder, circadian rhythm sleep arousal disorder, parasomnia)
• Those who have insomnia due to physical illness or medications being taken
• Patients with major medical and neuropsychiatric diseases other than sleep disorders
• Persons who have had or are currently undergoing dental treatment with a history of implanting metallic materials into the upper body, such as the transcranial or face, neck, etc., where non-invasive electrical stimulation is difficult or impossible
• Compliance was evaluated by writing a sleep diary for 1 week from the start of treatment, and if a sleep diary of 3 days or less was kept for 1 week, it was excluded from the study.
• Those who have changed the type and dose of drugs used within the last 3 months, or the type and time of cognitive behavioral therapy
• If you are currently registered in another clinical trial or use another clinical trial drug or device within 60 days from the time of screening

Exclusion criteria prior to intervention (After the sleep diary for one week after the screening test, if the following criteria are met, the patient will be excluded from participation in the study before the intervention.)

• Those with less than 8 points based on the Korean version of Insomnia severity index (ISI-K)
• When writing a sleep diary for a week, if it is written for less than 3 days or has an irregular sleep schedule