Background Caring for a family member with dementia puts caregivers at risk for depressive symptoms. Yet, interventions with promising effects on caregiver depressive symptoms are not well documented. Aims This review aimed to examine the quality and effectiveness of interventions to reduce depressive symptoms reported by caregivers of people with dementia. Design A systematic review and meta-analysis of nonpharmacological intervention trials was conducted. Methods The electronic databases searched included MEDLINE, CINAHL, and PsycINFO to find randomized controlled trials published between 2007 and 2017. A total of 31 randomized controlled trials were included in the meta-analysis. Results Cognitive-behavioral therapy (838 participants) showed a large, significant effect (standardized mean difference = -0.905; 95% CI = (-1.622, -0.187); p = 0.013) and mindfulness interventions (186 participants) showed moderate, significant effects (standardized mean difference = -0.578; 95% CI = (-0.881, -0.275); p < 0.001) on decreasing caregiver depressive symptoms, while psychoeducational interventions demonstrated small but significant effects (standardized mean difference = -0.244; 95% CI = (-0.395, -0.092); p = 0.002). Emotional support, cognitive rehabilitation, and multicomponent interventions showed less than small or nonsignificant effects related to depressive symptoms among caregivers. Conclusion Cognitive-behavioral therapy interventions, which focus on diminishing negative thoughts and increasing positive activities, can effectively decrease depressive symptoms for caregivers of individuals with dementia. Future research is recommended to assess the long-term effectiveness of cognitive-behavioral therapy in this population.