In the high-quality development stage, the data economy has become an important tool for achieving common prosperity. Using provincial panel data from 2011 to 2021 and treating the implementation of national-level big data pilot zones as a quasi-natural experiment, the policy’s impact on common prosperity was analyzed through a difference-in-differences approach. The results show that the policy significantly promotes the process of common prosperity. Further analysis reveals that the policy’s effect is more pronounced in western regions and large cities, with labor productivity acting as a mediator in this process.