The accounting literature is silent about how digital transformation can be transformed into outstanding business performance through cloud-based accounting effectiveness (CBAE) under the supervision of digital leaders. In the digital age, this mechanism is practically significant for emerging market firms to promote accounting practices and decision-making effectiveness. Thus, this study investigates how CBAE and decision-making quality (DMQ) mediate the impact of digital transformation on firm performance. In addition, the moderating effects of digital leadership on the relationships between digital transformation and CBAE and those between CBAE and DMQ are investigated. The proposed model and its hypotheses are evaluated using partial least squares structural equation modeling (PLS-SEM) on survey data from 252 large-sized Vietnamese firms. The study's findings are as follows: (1) digital transformation positively affects CBAE, which affects DMQ and firm performance; (2) when digital leadership is strong, the effects of digital transformation on CBAE and CBAE on DMQ are amplified. These findings demonstrate how the interaction between digital transformation and digital leadership can contribute to the success of firms in emerging markets that use cloud accounting. In addition, the current study elucidates the mechanism by which digital transformation influences the digitalization of accounting practices and contributes to our understanding of digital transformation research in accounting by introducing digital leadership as a boundary condition.