BackgroundClimate change poses a substantial threat to the mental wellbeing of young people. Population-level research is urgently needed to help inform policies and interventions to ensure that young people are not burdened by long-term mental health impacts from climate change. We sought to identify the prevalence, distribution, and factors associated with climate change-related mental and emotional health outcomes among young people (aged 13–34 years) in Canada. MethodsThis study is part of a larger cross-sectional survey, which examined mental and emotional health responses to climate change among individuals aged 13 years or older from across Canada. We used a multi-stage, multi-stratified random probability sampling procedure. Participants were randomly recruited through either an addressed letter or a telephone call. Online and telephone questionnaires were used to interview individuals in English, French, or Inuktitut between April 1, 2022, and March 31, 2023. Data were weighted by age and province using population estimates from Statistics Canada and analysed using descriptive statistics, factor analyses, and multivariable regression analyses. FindingsThe full survey included 2476 participants, with a subgroup of 409 young people. Of the 401 respondents who provided their gender identity, 215 (54%) identified as cisgender women, 167 (42%) identified as cisgender men, and 19 (5%) identified as non-binary. Preliminary results suggest that young people in Canada experience a wide range of climate-related emotional and mental health outcomes. More than 70% of respondents in the young people subgroup reported having at least mild levels of sadness, anger, worry, anxiety, concern, helplessness, hopelessness, or powerlessness related to climate change. The severity of climate-related emotional responses differed by gender, with non-binary respondents and cisgender women reporting higher average levels of distress than cisgender men. Regional differences were also observed, with northern regions and urban locations reporting more severe reactions. InterpretationThis study builds on the understanding of the burden of climate change on the mental health of young people. If unaddressed, the impact of this burden could have long-standing and wide-reaching public health and related socioeconomic effects. FundingCanadian Institutes of Health Research, ArcticNet, Social Sciences and Humanities Research Council Doctoral Fellowship, Izaak Walton Killam Memorial Scholarship, and Alberta Innovates Graduate Student Scholarship.