Currently, China is moving towards the era of the digital economy, which is gradually becoming a new engine of high-quality development. In the “double carbon” strategy context, the digital economy is characterized by low carbon emissions and high permeability, making it essential for carbon emission reduction. There needs to be more empirical research on the digital economy and carbon emissions. Given this, this study empirically examines the impact of digital economy development on carbon emissions intensity and its mechanisms in a multidimensional way based on the panel data of 30 provincial-level administrative regions in China from 2011 to 2019, utilizing a fixed-effects model, a mediated-effects model, a spatial Durbin model, and other methods. The study results show that (1) the digital economy can significantly reduce carbon emissions intensity. (2) The digital economy can indirectly affect the intensity of carbon emissions through industrial structure, energy structure, and environmental regulation. (3) The development of the local digital economy has a positive spillover effect on the carbon emissions intensity of neighbouring places. However, the overall effect is negative. This paper reveals some new features of the digital economy and carbon emissions intensity, which provides a reference for advancing the country’s construction and realizing China’s “double carbon” goal.