Climate change can have detrimental effects on children’s health and well-being. Despite the imperative to better understand how climate change affects children’s health and well-being, a systematic approach and focus exclusively on children (aged <18 years) is lacking. In this scoping review, we conducted a literature search on the impacts of climate change on children’s health from January 2000 to June 2019. The included studies explicitly linked changes in exposure to a risk factor for children’s health to climate change or climate variability. A total of 2970 original articles, reviews and other documents were identified, of which 371 were analysed. Our analysis, using an expanded framework, showed that the effects of climate change on children’s health operate through direct and indirect pathways with implications for the determinants of children’s health, as well as morbidity and mortality from a range of diseases. This understanding can be further strengthened by using a broader range of research methods, studying overlooked populations and geographic regions, examining the costs and benefits of mitigation and adaptation on child health, and considering the positioning of climate change and child health within the United Nations Sustainable Development Goals. Current and future generations of children are bearing and will continue to bear an unacceptably high burden of disease caused by climate change. ( Daniel Helldén, MD, Camilla Andersson, MSc, Prof. Maria Nilsson, PhD, Kristie L Ebi, PhD, Prof. Peter Friberg, PhD, Tobias Alfvén, PhD, more at www.thelancet.com)