Paddy fields are a significant source of agricultural methane emissions, making the estimation of their emission levels and trends crucial for addressing climate change. However, current research on methane emissions from paddy fields at regional or national scales often lacks the application of high-resolution spatiotemporal data on rice distribution, leading to considerable uncertainties in the estimates. To address this gap, we have utilized the updated methodology for estimating methane emissions from paddy fields as outlined in the 2019 IPCC Guidelines for National Greenhouse Gas Inventories. This involved updating the distribution of rice cultivation across China and refining the daily emission factors (EF). Building on this foundation, we estimated the total methane emissions from China's paddy fields in 2015 and analyzed the regional characteristics of these emissions. The study reveals the following key findings: ① In 2015, the total methane emissions from China's paddy fields amounted to 7.541 (6.866–8.216) Tg CH4 per year. The central, southern, and eastern regions of China, which are the primary rice-growing areas, exhibited significantly higher methane emissions from paddy fields compared to other regions. The national average baseline daily emission factor ([EF]c) was determined to be 1.231 (1.121–1.341) kg CH4 per hectare per day, whereas the adjusted daily emission factor ([EF]i) averaged 1.764 (1.606–1.922) kg CH4 per hectare per day. ② The study also identified regions with higher baseline daily emission factors ([EF]c) , which were predominantly found in the southwest and southern parts of China. In contrast, areas with higher adjusted daily emission factors ([EF]i) were primarily located in the eastern and southern regions, indicating spatial variability in emission intensities. ③ The influence of human activities on methane emissions was evident, with significant increases in the adjusted daily emission factors ([EF]i) in the southern, eastern, and central regions of China. Conversely, regions such as the northwest and the Hong Kong-Macao-Taiwan areas experienced a notable decrease in these factors, underscoring the dominant role of anthropogenic factors in modulating methane emissions from paddy fields. This research enhances the understanding of daily emission factors for paddy fields across different regions, thereby refining the estimation of methane emissions from China's paddy fields. The findings provide valuable insights into methane emission dynamics in the context of climate change. Moreover, this study offers crucial quantitative data to support the agricultural sector in formulating effective methane emission reduction strategies and restructuring crop patterns in line with the dual carbon goals. In addition, the research highlights the importance of incorporating high-precision satellite data and ground-based observations to improve the accuracy of methane emission estimates. By integrating these advanced technologies, the study contributes to more effective climate mitigation strategies. Collaboration between policymakers, researchers, and farmers is essential to implement these measures and achieve significant reductions in greenhouse gas emissions from paddy fields, ensuring sustainable rice production while mitigating climate change impacts.