Digital transformation has become a critical strategic priority for small and medium-sized enterprises (SMEs), yet its success remains uneven due to limitations in leadership, organizational capabilities, and institutional support. This study investigates the impact of transformational leadership on digital transformation effectiveness (DTE), with a particular focus on the mediating roles of digital culture, innovation climate, and digital skills, as well as the moderating role of government support for digital transformation. Using survey data from 420 SMEs in Hanoi, Vietnam, and surrounding provinces, the study employs partial least squares structural equation modeling (PLS-SEM) to test a comprehensive research model. The results reveal that transformational leadership has a significant positive effect on digital transformation effectiveness, primarily through indirect pathways. Among the mediating mechanisms, digital culture emerges as the most influential driver, followed by digital skills and innovation climate. In addition, government support significantly strengthens the relationship between transformational leadership and digital transformation outcomes, while resource and organizational factors show limited direct effects. This study contributes to the literature by integrating transformational leadership theory, resource-based view, dynamic capabilities, and institutional theory into a unified framework. It highlights that successful digital transformation is driven not only by leadership but also by the alignment of organizational mechanisms and external support conditions. The findings provide important implications for both scholars and practitioners seeking to enhance digital transformation in SMEs.
