BACKGROUND AND OBJECTIVES: The application of mindfulness- and acceptance-based interventions (MABIs) for informal caregivers of people with dementia (PwD) is relatively novel, and the current state of the evidence base is unclear. This meta-analysis examined the effectiveness of MABIs on reducing symptoms of depression and burden in informal caregivers of PwD. The quality of included studies was evaluated and moderator variables explored. RESEARCH DESIGN AND METHODS: A literature search of six electronic databases (PsycARTICLES, PsycINFO, MEDLINE Complete, SCOPUS, Web of Science, and ProQuest) was conducted from the first available date to 20 December 2016. Inclusion criteria involved studies that quantitatively investigated the impact of MABIs on depression and/or burden in informal caregivers of PwD. RESULTS: Twelve studies, providing data on 321 caregivers, were included. Most used mindfulness-based stress reduction and were conducted in the United States. The average attrition among participants was 15.83%. The pre-post effect of MABIs was large for depression and moderate for burden. These effects were largely maintained at follow-up. Significant heterogeneity of effect sizes was observed, with no significant moderators identified. Study quality varied from very poor to moderately good. DISCUSSION AND IMPLICATIONS: The low attrition and moderate to large effects suggest that MABIs are acceptable and beneficial for informal caregivers of PwD. The lack of significant moderators could advocate services using more cost-effective forms of MABIs. Further higher-quality research is needed to improve the robustness of the evidence base and enable a meta-analysis to thoroughly examine and quantify moderator variables.