Along with the rapid development of digital economy and the urgency of green development, more studies focus on the relationship between digital economy and green development. However, the existing research focuses on the impact of digital economy on green total factor productivity, ignoring digital technology, which is a key technology for improving efficiency to achieve green development. Exploring the impact of digital technologies on green total factor productivity helps to understand the impact of digital economic development on green development from an internal perspective of the digital economy. This paper uses an SBM-GML index to measure regional green total factor productivity based on provincial level data and innovatively constructs digital technology indicators based on microlevel ICT patent data in China. Fixed-effects model is used to study the impact of digital technology on green total factor productivity and moderating model is used to examine the moderating effect of capital accumulation. The results indicate that: (1) At the national level, digital technology is conducive to the improvement of green total factor productivity, and the result passes the robustness test. From a dynamic long-term impact perspective, the effect of digital technology development on green total factor productivity is showing an increasing trend. (2) Digital technology’s effect on green total factor productivity is heterogenous. The results of the subregional heterogeneity analysis indicate that the effect is greater in the coastal regions and southern regions. The results of the heterogeneity analysis of the external environment indicate that the effect is greater in regions with smaller economies, regions with lower external economic dependence, and regions with lower government fiscal intervention. (3) Capital accumulation has moderating effect in the process of digital technology affecting green total factor productivity which will inhibit the improvement of digital technology development on green total factor productivity. Based on the conclusions, to better utilize the role of digital technology in promoting green development, it is necessary for the government to build a digital technology exchange platform, promote the balanced development of digital technology, and expand domestic demand to reduce the dependence on capital accumulation.