Unite! Poster Competition is a worldwide student competition to review the sparks on architectural energy for low-carbon to sustainable development. First, the competition was launched based on global environmental problems such as climate change and related policy guidance such as a series of guidance from the United Nations. Then, 12 posters from 10 universities worldwide were collected. The authors initially sorted out the related low-carbon strategies, and the related SWOT analysis were also summarized. The third section analyzed the evaluation contents of 15 judges. The jury characteristics, evaluation procedure and related comments are studied. Finally, the research got the ranking list of the posters. The fundamental analysis of the posters by authors compared with the scores and comments from professional judges to verify the rationality of the results. Then, more profound low-carbon revelations are sorted out. In this research, there are also some limitations, such as the wording problem of the “poster” use and overly broad requirements for the call for posters. However, the research is conducive to researching and promoting low-carbon development and also realizes closed-loop research on mitigating background problems.