Abstract: Scientifically evaluate the changing trend, temporal and spatial distributions and influencing factors of carbon (C) sinks in the "Lucid Waters and Lush Mountains are Invaluable Assets" practice and innovation bases plays an important role in guiding the construction of ecological civilization in the new era. Taking Ninghai County in Zhejiang Province as an example, this study measured C sinks and emissions in Ninghai County based on the IPCC C emission inventory, explored the spatial distribution of regional C sinks, and analyzed the influencing factors of C emissions in Ninghai County based on variance decomposition analysis. The results show that during the study period the C sink in Ninghai County showed a trend of increasing year by year, from 43.91×10⁴ t in 2003 to 49.40×10⁴ t in 2018, of which the forest C sink accounted for 88.21%-91.12%; the C source maintained stable during 2003 to 2006 and then increased sharply from 2007 to 2011, followed by a post-volatility decline and finally a stable trend, changing from 154.17×10⁴ t in 2003 to 508.87×10⁴ t in 2018. From the perspective of the spatial distribution of C sinks, the county-level C sinks in Ninghai County roughly showed a pattern of "west high and east low": "west > southeast > north > central"; C emissions in Ninghai County could be jointly explained by social factors, economic factors and "Lucid Waters and Lush Mountains are Invaluable Assets" construction driving factors, and the total explanation degree of these three factors was 60.86%, of which economic factors > "Lucid Waters and Lush Mountains are Invaluable Assets" construction driving factors > social factors. This research provides new ideas for the accounting of C sources and C sinks in the national "Lucid Waters and Lush Mountains are Invaluable Assets" practice and innovation bases, as well as provides a reference for the future policy formulation and green development for the county.