Poverty alleviation programs, such as cash transfers and monetary grants, may not only lift people out of poverty but, some argue, may improve mental health as well. However, to date, the impact of such programs on children and adolescents' mental health is unclear. We carried out a sys-tematic review and meta-analysis of poverty alleviation interventions providing monetary support and reporting mental health outcomes in 0-19 year olds in low-, middle-, and high-income countries. We searched 11 databases for research published between January 1, 1990 and June 1, 2020 and included interventions offering unconditional and/or conditional monetary support and reporting mental health outcomes. After screening 7,733 unique articles, we included 14 papers (16,750 children and adolescents at follow-up) in our narrative summary. We meta-analyzed data on internalizing symptoms from 8 papers (13,538 children and adolescents analyzed). This indicated a small but significant reduction in adolescents' internalizing problems post -intervention compared to control (odds ratio 0.72, 95% confidence interval 0.59-0.88, p < .01; I-2 = 67%, tau(2) = 0.05, p < .01). Our narrative synthesis provides further support for the overall effectiveness of cash programs but also notes that monetary support alone may not be suf-ficient in extreme risk settings and that imposing conditions may be actively harmful for the mental health of adolescent girls. We provide causal evidence that monetary interventions reduce internalizing symptoms of adolescents experiencing poverty. We recommend that future programming thoughtfully considers whether to apply conditions as part of their in-terventions and highlight the importance of providing additional comprehensive support for children and adolescents living in extreme risk settings. (C) 2022 The Authors. Published by Elsevier Inc. on behalf of Society for Adolescent Health and Medicine.