<p>How digital transformation affects the innovation efficiency of enterprises has become an important topic to be studied in the context of the new global scientific revolution. This paper constructs a theoretical digital transformation framework to promote improvements in enterprise innovation efficiency and uses the panel data of China’s A-share listed companies from 2015 to 2021 to test both the impact of digital transformation on the innovation efficiency of enterprises and the mechanism of enterprise organization with regard to flexibility, the opening up of innovation networks and the upgrading of market demand. The results show that: (1) Digital transformation plays an important role in improving the efficiency of enterprise innovation. After a series of robustness tests, including tool variable tests, Propensity Score Matching-Differences-in-Differences (PSM-DID), and other endogenous tests, the conclusions are still valid. (2) The experimental results to determine the mechanism show that digital transformation promotes the efficiency of enterprise innovation by increasing the flexibility of enterprise organization, promoting open innovation by enterprises, and promoting the upgrading of market demand. (3) The results of heterogeneity analysis show that the promotion effect of digital transformation on the improvement of enterprise innovation efficiency is more significant in those competitive enterprises that are non-state-owned, in the Eastern region, technology-intensive, and in medium-level industries. These results mean not only that digital technology has become an important engine of innovation-driven development, but also that digital transformation is an important way to solve the "low-quality and inefficient" innovation dilemma of enterprises.</p>