AbstractAimsTo investigate the efficacy of applying auricular acupuncture (AA) treatment in improving dry mouth in institution‐dwelling older adults.BackgroundDry mouth (xerostomia) is a common distressing problem in older populations, especially for institution‐dwelling older adults that can affect oral health and quality of life.DesignA randomised controlled trial was conducted from December 2020 to March 2021 and performed according to STRICTA guidelines extended from the CONSORT statement.MethodsOlder adults aged more than 65 years were randomly allocated to an AA group (n = 37) with an 8‐week actual auricular points treatment or a control group (n = 38) receiving sham auricular point acupuncture. Measurements comprised a subjective assessment of the level of dry mouth as assessed by a visual analogue scale in a xerostomia questionnaire, and an objective assessment of the physiological wetness of the lingual mucosa measured with a moisture‐checking device. A generalised estimating equation model was used for data analyses.ResultsAfter completing an 8‐week AA intervention stimulating the Shenmen, Point Zero and Salivary Gland 2‐prime points, the AA group exhibited significantly improved subjective symptoms of dry mouth comprised of difficulty speaking (B = −6.47, p < .001), difficulty swallowing (B = −6.73, p < .001), the amount of oral saliva (B = −5.38, p < .001), a dry throat (B = −7.53, p < .001) and thirst (B = −8.06, p < .001) compared with the control group. Moreover, the AA group had higher objective oral saliva flow than the control group (B = 4.73, p < .001).ConclusionAA is an effective non‐pharmacological method for improving subjective symptoms of dry mouth and objective saliva secretion in older populations living in nursing homes.Relevant to clinical practicePerforming regular AA on the Shenmen, Point Zero and Salivary Gland 2‐prime auricular points can be considered an alternative treatment approach to improve dry mouth in institution‐dwelling older adults.