OBJECTIVES: This systematic review examined empirical evidence of the effects of relaxation interventions on anxiety and depression among older adults. METHOD: A comprehensive literature search identified studies that satisfied the pre-set inclusion and exclusion criteria. We focused on 15 published and non-published studies - 12 randomised controlled trials and three non-randomised controlled trials - undertaken in the past 20 years (1994-2014). Three reviewers selected studies, extracted data, and appraised the methodological quality. We then computed Hedges' effect sizes and used these to represent the effects of intervention. RESULTS: Our findings suggested that older adults who received relaxation interventions experienced greater reductions in depression and anxiety than controls in most studies. Progressive muscle relaxation training, music intervention, and yoga had the strongest intervention effects on depression. Music intervention, yoga, and combined relaxation training most effectively reduced anxiety symptoms among older adults. Furthermore, the impact of some relaxation interventions remained in effect for between 14 and 24 weeks after the interventions. CONCLUSION: This systematic review supported the positive effects of relaxation interventions on depression and anxiety among older adults. Health care providers may integrate relaxation interventions into standard care for older adults in community and hospital settings, taking into consideration the participant's preference and health care policy.