Background <p>Climate change is a risk multiplier for mental health that compounds existing social and health inequities. Aotearoa New Zealand (Aotearoa hereafter) carries a high mental-health burden, with rangatahi Māori (Māori youth) disproportionately affected. International studies link negative emotional responses to climate change with perceived government inaction, yet representative data are lacking in Aotearoa.</p> Methods <p>A cross-sectional online survey of 1167 youth (aged 16–25) in Aotearoa was conducted between September and October 2024. Participants reported on climate worry, climate-related emotions, daily functioning, and perceptions of government responses. Data were weighted to population benchmarks. Descriptive statistics, group comparisons (by gender and ethnicity), multivariable regression models, and Spearman’s correlation analyses were conducted.</p> Results <p>Negative climate-related emotional responses were common. Over half of respondents reported sadness, helplessness, powerlessness, anxiety, fear, and anger. Overall, 66.1% reported at least moderate climate-related worry, and 35.6% reported feeling very or extremely worried. Around half reported impaired daily functioning. Government responses were viewed more negatively (57.7%) than positively (39.1%), with feelings of betrayal exceeding reassurance. Climate-distress indicators were moderately associated with more negative perceptions of government responses. Rangatahi Māori commonly endorsed anger and negative government perceptions, alongside lower endorsement of some threat-related emotions such as anxiety, fear and powerlessness.</p> Conclusions <p>Climate-related emotional responses among youth in Aotearoa are widespread and are associated with more negative perceptions of government climate action. Findings highlight the importance of policy responses that are transparent, equitable, and developed in partnership with young people, including approaches grounded in Indigenous perspectives.</p>