High compliance with methadone maintenance therapy (MMT) is crucial to successful opioid abstinence in addicts. However, MMT has numerous side effects, including reductions in quality of life and quality of sleep. Many studies have demonstrated that electroacupuncture relieves withdrawal symptoms in opioid addicts. The present study was a case-control study. From January 2015 to September 2016, 106 patients undergoing MMT at a medical center in central Taiwan were recruited and separated into an electroacupuncture treatment group and a control group. Electroacupuncture was performed for 15 minutes twice weekly for 4 weeks. The electroacupuncture treatment group was discovered to have improved quality of life, especially in terms of vitality and mental health. Although electroacupuncture did not significantly improve sleep quality, we found that sleep quality was significantly improved once methadone dosage had been reduced. Electroacupuncture can improve quality of life in patients undergoing MMT. If methadone dosage can be reduced and electroacupuncture can be employed, both sleep and life quality can be improved.