Objective: We examined the effects of MMIs on depression in older adults and explored the moderating effects of participant, methods, and intervention characteristics. Methods: We systematically searched 15 databases through June 2019 without date restrictions using the following search terms: (mindful* OR meditat*) AND depress* AND (older adult* OR elder OR aging OR senior OR geriatric*). Inclusion criteria were primary studies evaluating MMIs with adults ≥65 years old with depression measured as an outcome, a control group, and written in English. Two researchers independently coded each study and compared for discrepancies and consulted a third researcher in cases of disagreement. We used random-effects model to compute effect sizes (ESs) using Hedges' g, a forest plot, and Q and I2 statistics as measures of heterogeneity; we also examined moderator analyses. Results: Nineteen studies included 1,076 participants (71.8 ± 5.2 years old). Overall, MMIs showed significantly improved depression (ES=.65, 95%CI 0.35, 0.94) compared to controls. With regards to moderators, Asians had a greater improvement in depression (1.28) than Europeans (.59) and North Americans (.32). Less than 5 weeks of MMIs showed greater improvement in depression (1.47) than longer periods (.55). MMIs with guided meditation reduced depression (.91) more than MMIs without (.42). Only one quality indicator, a priori power analysis, showed greater effects on depression (g = 1.0) than no power analysis (g=.35). Conclusion: MMIs improved depressive symptoms in older adults. MMIs might be used as adjunctive or alternative to conventional treatment for depressed older adults.