["Child and Adolescent Mental Health, EarlyView. ", "\n\nBackground\nAs the impacts of the climate crisis escalate, adolescents face increasing threats to their health and well‐being. However, little is known about the extent to which young adolescents experience climate worry (both in its general affective response and its specific cognitive concerns) and whether it is distinguishable from generalized anxiety. This study examined the prevalence of climate worry in young adolescents and tested its association with mental health and well‐being while controlling for generalized anxiety.\n\n\nMethods\nYoung adolescents (n = 1230; Mage = 12.85, 49% boys) from the All Our Families (AOF) pregnancy cohort completed questionnaires about affective and cognitive climate worry, mental health, well‐being, digital media use, physical activity, and sleep. Mothers completed questionnaires about demographics and their child's mental health.\n\n\nResults\nEleven percent of adolescents reported high to extreme affective climate worry, 23% moderate worry, 26% a little worry, and 40% no worry. Girls and gender‐diverse adolescents endorsed higher levels than boys. Correlation analyses revealed significant associations between affective and cognitive climate worry and maternal‐reported generalized anxiety (r = .12 and .18, respectively). Regression models showed that both were uniquely associated with elevated levels of depression, social media addiction, and sleep disturbance, as well as decreased optimism and happiness, even after adjusting for generalized anxiety.\n\n\nConclusion\nClimate worry appears to be distinct from generalized anxiety and uniquely predicts adolescent mental health and well‐being. Given that almost two‐thirds of adolescents report some level of climate worry, targeted efforts to address these concerns are warranted.\n\n"]