Climate change worry (CCW) is a specific worry about climate change, involving thoughts about changes that might occur in the climate system and their possible effects. Nowadays, it is growing especially among adolescents. As there is a lack of measurement tools with adequate psychometric properties to assess CCW in this age group, we investigated the psychometric properties of the "Climate Change Worry Scale" (CCWS) in youth. Participants were 1,846 Italian adolescents (58% males; mean age = 16.37; SD = 1.27). The expected unidimensional structure was supported by cross-validation with a multigroup confirmatory analysis, and measurement invariance of the scale across sex and age groups. Sex and age differences were analyzed. The CCWS had a high internal consistency, and good validity. Overall, this study contributes to attest that the CCWS is a suitable instrument for measuring CCW in adolescents.