Climate change has in recent years become an environmental issue globally. Through deepening research into and analysis of the phenomenon, most climate scientists now identify greenhouse gases, most notably CO_2 emissions, as constituting the main cause of global warming. Based on literature study and comparative analysis, this article discusses the progress of the research of CO_2 emissions from a multidisciplinary perspective and analyzes the calculation methods, intensity, performance, influencing factors, and forecasting methods of CO_2 emissions. This article also discusses the remaining issues and future directions of the research on CO_2 emissions. Results indicate that the research of CO_2 emissions has gained fruitful achievements and has experienced rapid development in recent years. CO_2 emission is an integrated, complex, interdependent system engineering of numerous variables interplay between different factors. Under the framework of multidisciplinary integration, geographical and spatial factors have however received insufficient attention. Research scale has mainly focused on global and international levels, although recent studies have begun to highlight multi-scale research and pay attention to scale effect. Panel study of provincial and city scales is still scarce. Panel data are gradually receiving attention; however, dynamic analysis and comparative assessment still need improvement. Future research should focus on creating more detailed and comprehensive datasets, exploring multi- scale integrated research, and highlighting city scale analysis. Furthermore, future study should emphasize adapting theories to localized practices, employing systemic thinking and methods for differentiated trend research.