Data governance serves as the foundation for unlocking the value of data and offers new opportunities for enterprises to reshape their market competitiveness in the digital era. The establishment of regional big data administration provides a practical basis for examining whether data governance generates interdepartmental institutional benefits. Based on the M-O model, this paper constructs a theoretical framework to analyze the impact of data governance on firm markups and conducts empirical tests using city-level panel data from 2007 to 2022 combined with the multi-period DID method. The results show that data governance can significantly enhance enterprise market competitiveness. Technological upgrading, spatial agglomeration of production factors, and reductions in institutional costs are key channels through which benefits are transmitted across departments. However, the effectiveness of such transmission is constrained by local governments’ governance willingness, intensity, and capacity, and exhibits uneven effects across enterprises, industries, and regions. Accordingly, efforts should be made to expand reform implementation, tailor policies to local governance differences, clarify responsibilities, and strengthen interdepartmental coordination. These steps will help empower, upgrade, and improve the efficiency of enterprise development through data, supporting enterprises in becoming stronger and more competitive, and enabling them to better integrate into global markets.