Abstract: The coupling and coordinated development of ecosystem services and people's well-being is crucial for the management and sustainable development of regional ecosystems. Taking the Karst-Beibu Gulf in southwestern Guangxi as an example, based on the modified model, comprehensive evaluation model and coupling coordination model, the coupling relationship between ecosystem services value (ESV) and the level of people's well-being was analyzed. The results showed that from 2005 to 2020, the ESV of the Karst-Beibu Gulf in southwestern Guangxi decreased, showing a spatial characteristic of "higher in the northwest and lower in the southeast", achieving a high level of people's well-being. The coupling and coordination between ecosystem services value and people's well-being had been enhanced, and the spatial distribution was consistent with the characteristic of ESV "high in the northwest and low in the southeast". From 2025 to 2035, the ESV shows a decreasing trend, while people's well-being and the coupling of the two will increase. However, measures should be taken to address the risk of ecosystem service value reduction. The research results have enriched the analytical perspective of people's well-being, proposing suggestions for implementing the adjustment of the occupation and compensation of construction land and ecological land, strengthening the construction of coastal protective forests, and guiding capital to fully convert the ecological value into economic and cultural value, to achieve ecological sustainability and stable growth of people's income.