Collective teacher innovativeness has emerged as a recent topic of interest in both international policy documents and scholarly research. However, only a few studies have focused on the factors that enable collective teacher innovativeness, particularly in terms of revealing whether and to what extent school leadership might influence this construct. Existing literature suggests that distributed leadership can influence teachers' instructional practices, emotions, and daily activities, all of which could be important to teacher innovativeness. The present study, therefore, aimed to explore the effect of distributed leadership in fostering collective teacher innovativeness, as well as the mediating roles played by job satisfaction and professional collaboration, by using the Teaching and Learning International Survey 2018 dataset. The findings of the partial mediation structural equation model analysis revealed that distributed leadership has both direct and indirect effects on collective teacher innovativeness, as mediated by job satisfaction and professional collaboration. The results provide evidence of how principal leadership practices impact teachers' changes in behaviors through professional attitudes and practices.