<p>In the context of the high-quality development, environmental regulation (ER) has become an important factor to promote the transition from old to new drivers in marine economy. This paper constructs a comprehensive marine environmental regulation index by integrating command-and-control, market-incentive and public participatory marine environmental regulation. It measures the level of transition from old to new drivers in marine economy using the entropy method and employs benchmark regression to verify the driving effect of ER on the transition. The findings are as follows: (1) ER shows an increasing trend and has phased characteristics, and there are large regional differences of ER in three major marine economic circles. (2) The level of the transition from old to new drivers in marine economy is low, and there is a large potential for development. (3) ER can significantly promote the transition from old to new drivers of the marine economy. However, ER has a spatial heterogeneity in its impact on the transition from old to new drivers in marine economy, and the three types of ER also show spatial differences in the direction and degree of their impact. Meanwhile, the effect of ER on the transition in the marine economy undergoes a gradient transition from negative to positive, influenced by the level of development of the marine economy. Marine technological innovation is an intermediary variable for ER to promote the transition process. It is necessary to improve marine regulatory construction, promote marine technological innovation, and realize regional coordination and cooperation in coastal areas, so as to accelerate the process of new and old drivers transition in the marine economy.</p>