Most research on open innovation focuses on innovation performance. However, few people have explored the driving factor of open innovation. This study is based on the entrepreneurial perspective, combined with the new institutional theory, taking 243 A-share listed military-civilian integration companies in China from 2016-2020. A multiple linear regression method is used to discuss the influence of entrepreneurial orientation on the open innovation of military-civilian integration enterprises, and the mediating role of organizational legitimacy. The empirical research results show that: entrepreneurial orientation positively influences the open innovation of military-civilian integration enterprises; political relevance plays a mediating role in the influence of entrepreneurial orientation on open innovation; compared with the military-to-civilian enterprises, political relevance is more important to the civilian-to-military enterprises. The research findings can not only enrich the open innovation theory but also have an important guiding significance for the military-civilian integration technology innovation in China.
