Climate change poses a threat to children, who are increasingly vulnerable, depending on adults to protect them from the impacts of these changes including extreme weather events, poor air and water quality and risk to mental health. Children living in poverty carry additional burdens and risks, living in environments that consistently experience poor air and water quality from polluting industries, compounded by the effects of climate change. COVID-19 has placed additional challenges to children's health and increases the complexity of addressing climate change and environmental justice. The intersection between climate change and COVID-19 exacerbates these existing disparities by impacting children's physical and mental health that are a direct product of poverty and structural racism. This article examines the nexus of climate change, COVID-19, and environmental justice that impacts the mental and physical health of children including anxiety, stress, adverse childhood experiences, and depression; increases in violence and aggression; and the effects of air pollution. Public health professionals and health care providers must be aware of national strategies that protect children from environmental health risks and emerging infectious diseases, such as climate change and COVID-19, respectively. Key Take Away Points: (1) Anthropogenic climate change poses a threat to the health of children, especially of those in marginalized communities; (2) COVID-19 has exacerbated these detrimental health impacts for children experiencing the effects of climate change; and (3) There are opportunities to protect children's health through equitable polices and programs.