In the context of dual carbon goals and new urbanization, ensuring stable economic growth while reducing carbon emissions is one of the important tasks to achieve high-quality urban development, and it is also one of the key construction goals of national low-carbon pilot cities such as Changsha, Zhuzhou and Xiangtan. Therefore,taking the central urban area with the most drastic land use changes and carbon emissions in the Changsha-Zhuzhou-Xiangtan urban agglomeration as the research area, on the basis of the current situation analysis, the Markov-PLUS coupling model and carbon emission response model are used to simulate the expansion of construction land and carbon emission response under the existing trend development scenario, the development scenario of arable land protection, the green and low-carbon development scenario, and the rational development and construction scenario. The results show that:①From 2000 to 2020, the construction land area of Changsha-Zhuzhou-Xiangtan urban agglomeration showed a trend of periodical fluctuation growth. Cultivated land and forest land were the main sources, and the expansion intensity was the largest from 2010 to 2015, mainly concentrated in the central area of the urban agglomeration. The carbon emissions showed an inverted "V" shaped curve, which could be divided into two stages:rapid rise of carbon emissions (2000-2005) and decline of carbon emissions (2005-2020). With 2010 as the node, the decline rate first increased and then slowed down. There is a relatively close positive correlation between construction land area expansion and carbon emission, the overall performance is a strong expansion of construction land area increase (decrease) carbon emissions increase (decrease) and higher emission mode.②The results of Markov-PLUS simulation show that the expansion area of construction land is the largest (235.9503km²) under the natural development scenario, and the smallest (200.6354km²) under the ecological protection development scenario. Under the scenario of green and low-carbon development, the ecological carbon sink area occupied by construction land expansion is less than the other scenarios (169.78km²), accounting for more unused land (1.20km²) than other scenarios. The distribution of expansion is more reasonable, and the pressure of ecological environment and carbon emission is less, which is conducive to ecological environmental protection and social and economic development. ③Carbon emission response results displaced that under different scenarios, the carbon emissions of each district and county present certain sensitivity to the expansion of construction land. Integrating construction land expansion and carbon emission response results, the green and low-carbon development scenario is the better development model of Changsha-Zhuzhou-Xiangtan urban agglomeration in the future.