The literature search was conducted in PubMed, Embase, Cochrane Library databases, Clinicalkey, China National Knowledge Infrastructure (CNKI), China Scientific Journal Database (VIP), Wanfang Database and Chinese Biomedicine (SinoMed) covering the period from inception to June 2018. Following the Participants, Interventions, Comparisons, Outcomes and Study design (PICOS) principle, the key search terms included hypertension, high blood pressure, essential hypertension, auricular therapy, ear acupoint, acupressure, acupuncture, electroacupuncture, bloodletting, laser acupuncture, lasering, moxibustion and random.