To explore the core mechanisms of green synergistic development in China in the context of transition, this study takes 30 Chinese provinces and cities as a sample. Additionally, it is the first study to include digital finance, green finance, and ecological governance in the same research framework, and it innovatively explores the internal linkages between them from the perspective of systemic coupling and dynamic correlation. The study finds that the levels of digital finance, green finance, and ecological governance at the provincial level in China are all increasing to a certain extent. The coupling coordination degree between the three shows a development trend first rising and then falling in a transitional stage between barely coordinated and high-quality coordination, with developed regions having a higher coupling coordination degree, and less developed regions having a lower coupling coordination degree. From the dynamic correlation perspective, digital finance, green finance, and ecological governance all have a positive self-reinforcing effect, with the interaction effects being positively significant, except for the non-significant contribution of green finance to the level of digital finance and ecological governance. This study makes a series of theoretical suggestions that can optimize the transition path based on the reality of China's green development.