[Objective] The spatial differences and dynamic evolution of carbon ecological security level were analyzed to optimize the overall plan of carbon ecological security in the Yellow River basin (an important “energy basin” in China) in order to objectively reflect the current status and evolution trend of carbon ecological security, and to provide a reference for optimizing the carbon ecological security pattern. [Methods] An evaluation index system for carbon ecological security in the Yellow River basin was constructed under the framework of driving-pressure-state-impact-response (DPSIR) analysis. The technique for order preference by similarity to ideal solution (TOPSIS) model was used to evaluate the level of carbon ecological security, and the spatial-temporal evolution characteristics were analyzed by the kernel density estimation method. [Results] ① Carbon sinks and carbon emissions increased from 2012 to 2021 in the Yellow River basin, and the growth rate of carbon emissions was faster than that of carbon sinks. Carbon sinks were spatially characterized as “higher in the west and lower in the east”, while carbon emissions were “lower in the west and higher in the east”. ② The carbon ecological security level in the Yellow River basin increased over time, from 0.356 in 2012 to 0.639 in 2021. In terms of spatial distribution, the carbon ecological security level in the upstream region was higher than in the middle and downstream regions, and was characterized as “upstream leading, midstream catching up, and downstream surpassing”. In addition, the level of carbon ecological security tended to be good. ③ Based on the kernel density estimation results, the differences in carbon security levels among different regions in the Yellow River basin were gradually narrowing, and were decreasing in the upstream region faster than in the middle and downstream regions. [Conclusion] Based on the current status of carbon ecological security in the Yellow River basin, carbon sink capacity in the upstream region is expected to increase over time, while clean energy industries and technology-intensive industries with high added value should be developed to promote green GDP growth in the middle and downstream regions. In addition, a carbon ecological compensation mechanism should be established to coordinate and resolve cross-regional security issues, and to improve the carbon ecological security level of the entire basin.