Abstract: Under China’s “dual-carbon” policy framework (carbon peak and carbon neutrality), agricultural emission reduction has become a crucial pathway for achieving sustainable development and environmental sustainability. This study systematically investigated the impact mechanism of digital agriculture on agricultural carbon emissions to provide comprehensive theoretical support and policy implications for the development of low-carbon agriculture. Based on a provincial-level panel dataset encompassing 30 Chinese provinces (autonomous regions and municipalities, excluding Hong Kong, Macao, Taiwan, and Xizang of China) from 2011 to 2020, this study used an integrated analytical framework incorporating two-way fixed effect, mediation effect, and threshold effect models to rigorously examine the complex relationship between digital agriculture development and agricultural carbon emissions. The empirical results robustly demonstrated that digital agriculture exhibited a significant and substantial “carbon reduction effect”. This conclusion remained statistically significant and economically meaningful after conducting a series of robustness tests, including replacing the core explanatory variable, data winsorization, and sample exclusion. Further mechanistic analysis revealed that farmland transfer was a critical mediating pathway through which digital agriculture achieved carbon reduction benefits, facilitating large-scale agricultural operations and technological adoption. The threshold model test revealed that when labor outflow was between the single and double thresholds, the inhibitory effect of digital agriculture on agricultural carbon emissions was more significant. When the scale of agricultural operations exceeded a single threshold value, the inhibitory effect of digital agriculture on carbon emissions became more significant. When industrial rationalization exceeded a single threshold value, the inhibitory effect of digital agriculture on carbon emissions became more significant. These findings have important policy implications for the low-carbon agricultural transition in China. During the critical acceleration phase toward achieving China’s dual carbon goals, policymakers should prioritize fully leveraging the “digital dividend” of agricultural digital transformation. Implementation strategies should focus on creating tailored region-specific models for digital agriculture promotion that align with local resource availability and developmental stages. Concurrently, innovative approaches must be actively investigated to enhance the synergy between digital technology adoption and emission reduction initiatives. This study advances sustainable agricultural research by offering empirical evidence and analytical frameworks to assess the carbon mitigation potential of digital agriculture in developing economies, and provides practical insights for coordinating agricultural digitization with environmental sustainability under China’s “dual-carbon” policy framework.