Climate change is a global environmental issue, and climate change beliefs have a substantial influence on adolescent pro-environmental behavior. Ensuring sustainable consumption and production models (Goal 12) and taking urgent action to address climate change and its influence (Goal 13) are explicitly stated in the United Nations Sustainable Development Goals. In this research, we make a large-sample survey in middle schools, Beijing. As a result of convenience sampling, 2016 valid questionnaires were collected (male students = 993, aged between 12 and 14 years). Multiple linear regressions and mediation models were used to test the effect of climate change beliefs (climate change occurrence, climate change attribution, and climate change risk perception) on adolescent food saving behavior and the intermediation of environmental concerns. The research finding that (1) climate change beliefs significantly and positively predicted adolescent food saving behavior in these areas: climate change occurrence, climate change attribution, and climate change risk perception, and (2) environmental concerns mediated the effect of climate change beliefs on the food saving behavior of secondary school students. The findings have enlightenment for policymaking and the education sector. The education sector should enhance adolescents' correct understanding of climate change by adopting certain activities and educational strategies, thereby reducing food waste behavior, cultivating a sense of conservation, and further enhancing adolescents' sense of social responsibility to contribute to environmental protection and sustainable development.