Based on the panel data of 12 prefectura-level cities in Hubei Province for a total of 22 years from 2000 to 2021, a two-way fixed-effects model was selected to study the impact and mechanism of productive service industry agglomeration on economic growth. It is found that the impact of productive service industry agglomeration on economic growth in Hubei is characterized by an inverted U-shape, and except for Wuhan at this stage, the other regions are in the first half of the inverted U-shape. From the results of the mechanism test, in the process of productive service industry agglomeration on economic growth, technological innovation is part of the mediating effect, and environmental regulation has a significant moderating effect. The impact of productive service industry agglomeration on economic growth is heterogeneous in sub-region and sub-industry.