Abstract: The integrated development of the sports industry and the digital economy is a critical topic for the high-quality growth of the sports industry in the new era. This study employs a double machine learning model to examine the impact of public data openness on the integration of the digital economy and the sports industry, while analyzing its mechanism from three perspectives: institutional transaction costs, sports factor allocation, and scientific and technological innovation. The findings are as follows: 1) Public data openness significantly promotes the integration of the digital economy and the sports industry; 2) public data openness drives this integration by reducing institutional transaction costs, mitigating the misallocation of sports factors, and enhancing the level of scientific and technological innovation; 3) heterogeneity analysis shows that public data openness has a stronger promoting effect on the integration of the digital economy and the sports industry in eastern provinces compared to central and western provinces; 4) extended analysis indicates that the quality improvement of public data openness platforms can promote the integration of the digital economy and the sports industry. Among these findings, due to the multi-source, real-time, and unstructured characteristics of sports data, data content quality exerts a stronger driving effect on the integration of the digital economy and the sports industry compared to platform service quality and policy support intensity. To better promote the integrated development of the sports industry and the digital economy, it is recommended that: 1) Strengthen the construction of public data opening platforms, focus on improving data content quality, and thereby enhance their driving role in the integration of the digital economy and the sports industry; 2) establish a unified sports data standard system and optimize the data governance structure to reduce institutional transaction costs and alleviate sports factor misallocation; 3) improve the data governance system, strengthen policy coordination and regulatory mechanisms, so as to enhance the governance efficiency of public data opening and support technological innovation; 4) strengthen the cultivation of interdisciplinary talents and build an education system integrating industry, academia, and research to fill the talent gap in the process of digital-sports integration.