Taking the data of China's 30 provinces from 2003 to 2020 as research samples, this paper constructs a dynamic panel model to explore the relationship between environmental governance and the development performance of green economy. Furthermore, this paper conducts the intermediary model to study the mediating effects that environmental governance acts on regional green economy developing performance through technical progress. The results show that there's a positive U shaped relationship between environmental governance and regional green economy developing performance, it means that environmental governance will firstly inhibit the development of green economy and then promote it; Technological progress plays an intermediary role in the impacts which environmental governance acts on the development performance of regional green economy, and technological progress can significantly promote the development performance of regional green economy; The impact of environmental governance on the development performance of green economy shows regional differences, southern regions show obvious positive U-shaped relationship while northern regions demonstrate non-significant relationship between them.