Abstract: Enterprise digital transformation is a process of cognitive reshaping of managers' thinking, but there is little literature on the process of enterprise digital transformation from the perspective of management cognition. Based on the upper echelons theory, our paper constructs the analytical framework of "cognitive flexibility-digital leadership-digital transformation", and proposes that managers' cognitive flexibility is a key cognitive characteristic that affects enterprise digital transformation, and digital leadership is a key path for cognitive flexibility to affect enterprise digital transformation. Meanwhile, integrating the trait activation theory, we further proposed that the externally-focused IT capabilities of the organization is a key contextual factor to stimulate the influence of cognitive flexibility. The results of empirical analysis found that cognitive flexibility promotes the construction of digital leadership and then has a positive impact on enterprise digital transformation, and externally-focused IT capabilities play a positive moderating role in the relationship between cognitive flexibility and digital leadership. This paper enriches the research on enterprise digital transformation from the perspective of management cognition, and provides theoretical guidance and practical guidance for enterprise digital transformation.