The discourse power theory of Michel Foucault, a French postmodernist thinker, reveals the constructive function and power characteristics of “discourse” as a social practice. Language, as a carrier reflecting social reality, is associated with power, society and ideology. This constructive discourse theory enlightens and studies many disciplines of Humanities and social sciences. Since the late 1980s, media discourse has attracted linguists’ attention as a language in use, as well as its special textual structure and social and cultural practice. Some analytical methods have emerged at the historic moment, and critical discourse research is one of them. It originated in the 1980s. With the development of a large number of studies, people find that it is far from possible to answer research questions only by analyzing a single text, and that analysis will bring personal prejudice. In order to make the research more comprehensive and reliable, people begin to use corpus. The method of studying large-scale texts has its own advantages and draws on each other’s strengths to complement each other’s weaknesses. In the past 10 years, corpus-based critical discourse research has been increasingly adopted by Chinese social scientists. This book focuses on the reports on low-carbon in the mainstream newspapers and periodicals of China, Britain and the United States since 2000. It analyses discourse construction around low-carbon, and systematically applies corpus and critical discourse analysis to media discourse analysis. Combine qualitative and quantitative research effectively. The linguistic examples provided by corpus are beyond the intuitive research method, and the critical discourse analysis method makes the examples provided by corpus clear. We find many interesting phenomena that need to be further investigated from word frequency information. Studies show that the analysis of word clusters and collocations, accompanied by corpus retrieval, adds qualitative elements to quantitative analysis and makes the results more reliable and comprehensive. The combination of corpus findings and social context makes us realize more clearly that discourse is the reflection of ideology. This study is expected to attract more scholars to apply this method to language-related research in the field of social sciences.