Climate change impacts human health throughout the human life cycle. Previous studies have confirmed that climate change, particularly temperature fluctuations, significantly affects adults' mental health. However, studies regarding the impact on adolescents are still lacking. This is particularly worrying because adolescents may be more susceptible to the effects of climate change than adults due to their physical and emotional immaturity and vulnerability. Here, we found that increases in average temperatures worsened adolescents' mental health, measured by the Kessler Psychological Distress Scale, using data from 2010 and 2014 China Family Panel Studies. This effect is robust to alternative measures of mental health. In addition, younger adolescents and those from lower socio-economic backgrounds are more vulnerable to temperature changes. We recommend developing public policies to help adolescents adapt with temperature changes, particularly for younger adolescents and those from underprivileged families.