In the era of digital economy, digital transformation has become the booster of industrial upgrading and high-quality economic development. As an important supplier of digital resources such as talents, knowledge and technology, universities play a key role in promoting the digital transformation of firms. Based on text analysis of the official website news of the Chinese A-share listed firms, an indicator is constructed to measure the degree of academia-industry-collaboration at the firm level. Then we empirically examine the promotion effect, internal mechanism and consequences of academia-industry collaboration on the digital transformation of firms. The results show that academia-industry collaboration significantly improves the digital transformation of firms, and the conclusion is still robust after considering endogeneity issues and a series of robustness tests. Mechanism analysis shows that the promotion effect of digital transformation is achieved through talent effects and innovation effects. The heterogeneity analysis shows that the more attention the government invests in basic research and scientific and technological talents, the stronger effect of academia-industry collaboration in promoting digital transformation. The effect is also more significant for high-tech industries and firms in regions with high marketization level. Further, academia-industry collaboration can promote the output of digital achievements by promoting digital transformation. Research conclusion not only reveals the impact mechanism of academia-industry collaboration on firm digital transformation in theory, but also provides useful guidance for academia-industry collaboration and digital transformation practice, and also has important implications for the formulation of relevant policies.