Abstract: The economic growth of Beijing, Tianjin and Hebei has not yet been decoupled from carbon emissions, and it is difficult to coordinate their economic development and carbon emission reduction. In order to alleviate such structural contradictions, based on the STIRPAT expansion model, path analysis is used to reveal the impact mechanism of factors such as factor circulation, industrial collaboration, and institutional intervention on carbon emissions in Beijing, Tianjin and Hebei from the perspective of supply side reform, and peak prediction is made by designing adjustment scenarios from the perspective of human, capital, technology and other factors. the results show that: (1) Changing the high carbon emission model of Hebei is an important foundation for effectively promoting the low carbon transformation of Beijing-Tianjin-Hebei; (2) Labor productivity, government intervention and economic growth all promote the carbon emission of Beijing-Tianjin-Hebei, while energy intensity and industrial structure upgrading and coordination all restrain its carbon emission. Capital efficiency promotes carbon emissions in Beijing, while curbs carbon emissions in Tianjin and Hebei. In addition, labor productivity and economic growth are important intermediary factors. (3)Under the balanced regulation scenario, the Beijing-Tianjin-Hebei, Tianjin and Hebei reached the peak on schedule. Under the capital regulation scenario, the coordinated regulation level of Beijing-Tianjin-Hebei is the highest, and the peak time of Hebei is 5 years ahead of schedule; Under the human resource regulation scenario, the coordinated regulation level of Beijing Tianjin Hebei is the lowest, and the overall peak time is delayed by 5 years.