Urban areas, with dense populations and concentrated consumption, are major contributors to CO₂ emissions, accelerating the progression of the Anthropocene. In this context, low-carbon city transformation is essential for sustainability and climate resilience. This transformation is a complex process requiring collaboration across sectors and stakeholders, with media serving as a crucial communication bridge connecting government, the public, and other actors. This study uses in-depth interviews combined with systems thinking and transdisciplinary insights to analyze media coverage and its role in China’s low-carbon city transition. Basing on our cases, this study finds that (1) diverse media reporting raises public awareness of climate and low-carbon issues, but in-depth analysis and scientific interpretation remain limited due to a shortage of trained climate journalists. (2) Visual formats like videos and animations effectively capture public attention, while in-depth written reports, especially from state media, exert greater influence on policy and industrial transformation. (3) Beyond information dissemination, media facilitate dialog among government, businesses, NGOs, and citizens, promoting collective action in low-carbon city transformation. However, challenges such as climate anxiety, misinformation, and algorithm-driven information gaps undermine trust and engagement. This study highlights the media’s vital role in raising awareness, influencing behavior, and connecting stakeholders, providing insights to support better policy decisions and climate communication strategies for sustainable urban futures.