Abstract: To understand hotspots and trends of carbon emission in China in recent 20 years, literatures about carbon emission research in China in recent 20 years were analyzed based on knowledge graph, which quantity was 5683, and authors, published organizations, literatures influence, factors affecting carbon emissions, results of carbon emission reduction, measures to reduce carbon emission and future research trends in carbon emission reduction were analyzed．Results showed that network of researchers involved in carbon emissions was closely connected and showed a certain special block．Research institutions were mainly composed of high-level and interconnected research institutions, which plaied a positive role in promoting carbon emission research．Research focus on carbon emissions was factors of carbon emission, impact of excessive carbon emission, measures to reduce carbon emissions．High-impact literature was mainly based on data analysis, among which the most frequently cited literature was cited 17029 times．Researches on impact of carbon emissions mainly focused on three aspects: climate change, agricultural development and economic development．Through development of a low carbon economy and policy lead to reduce carbon emissions．In the future, main fields of carbon emission research still included economy and ecology, in addition, carbon neutrality and emission peak would become a relatively concentrated hot topic．Results could provide a reference for future scholars in this field．