Mangroves provide vital ecosystem services, including fisheries support, carbon sequestration, and natural protection against coastal erosion, but their health consequences are less well understood. We study their impacts on mental health and cognitive functioning in Indonesia, which has the most extensive and biodiverse mangroves in the world. Decades of deforestation, fueled by climate pressures, oil palm expansion, and aquaculture, have led to widespread mangrove loss in the country, disproportionately affecting vulnerable coastal communities. By merging high-resolution satellite data on coastal land use change with individual-level panel data from the Indonesian Family Life Survey (IFLS), we find that a one-standard-deviation increase in local mangrove cover reduces the likelihood of clinical depression by 4.5 percentage points. These effects operate through reduced flood exposure, higher household income, and improved food consumption. We also find that restoration potential matters more than blue carbon potential, cash transfers, or social capital in shaping the mangrove-mental health relationship. Our results show that mangrove conservation and restoration can generate important local human capital and welfare benefits.