In recent decades, climate change has shifted from an environmental concern to a global human-rights crisis, especially for children. Its direct and indirect impacts — from pollution and ecosystem degradation to food and water insecurity, displacement, and physical and psychological harm — threaten core rights such as survival, development, health, education, and participation. General Comment No. 26 of the Committee on the Rights of the Child has for the first time recognized “the child’s right to a clean, healthy and sustainable environment” as an independent, binding right, underscoring the link between human rights and environmental protection. The ICJ’s Advisory Opinion on State obligations regarding climate change likewise requires States to observe principles of customary law, including the prohibition of transboundary harm, the precautionary principle, international cooperation, and the duty of prevention, and interprets non-compliance as a violation of human rights, including children’s rights. Using a descriptive-analytical method and drawing on treaties, case law, and treaty-body interpretations, this article clarifies States’ international obligations toward children in the climate crisis. The central question is: What duties do States have under international law to protect children amid climate change? The study finds that these duties have evolved into binding positive obligations, and their breach may constitute an internationally wrongful act and a direct violation of children’s rights.