In the era of digital economy, how enterprises achieve leapfrog development through the deep integration of digital transformation and technological innovation has become a key driving force to promote the formation of new quality productivity and promote high-quality economic growth. Based on the data of 30 provinces in China from 2011 to 2022, this paper empirically tests the impact of enterprise digital transformation on technological innovation by measuring enterprise digital transformation index and two-stage technological innovation efficiency based on the perspective of innovation value chain. On the basis of the theoretical explanation of its influence and mechanism, the multi-dimensional influence of digital transformation on the efficiency of technological innovation is further discussed. The results show that (1) Digital transformation significantly improves the efficiency of technological innovation, especially in the transformation stage of the result market. (2) The influence of digital transformation on technological innovation efficiency at different stages presents different trends. The basic research and development stage presents an “N-shaped” relationship, while the results transformation stage presents an “inverted U-shaped” relationship. (3) Considering the externality of technological innovation, this paper deeply analyzes the governance methods and means that the government can adopt in different stages of digital transformation and technological innovation from three dimensions: capital elements, public goods and awareness of rules.Overall, the research offers both theoretical insights and empirical evidence to enhance the impact of digital transformation on technological innovation efficiency. It also suggests a policy mix as a suitable approach to addressing the externality issues faced by firms in technological innovation.