Good school governance is basically about effective principal leadership used to create appropriate processes, systems, and management for ensuring the sustainability and continuity of schools. This research aims to examine the model of good school governance and to establish the correlation between good school governance and the principal's decision-making in Indonesian vocational school contexts. The samples of the present quantitative descriptive study were the vocational school principals, vice-principals, and teachers by considering the representation of all provinces in Indonesia. The data were gathered from a structured questionnaire survey of 838 respondents. The factor analysis was applied to bring out the latent variables representing the attributes, and later, the causality between these variables was established using structural equation modeling (SEM). The confirmatory factor analysis has shown that good school governance was constructed by six principles namely transparency, accountability, responsibility, autonomy, fairness, and participation. Empirically, the good school governance has impacted positively on the quality of the principal's decision-making. The research has affirmed that good school governance facilitates the participation of teachers and educational staff in the decision-making process. Furthermore, the good school governance improves the decision-making quality through the empowerment of teachers, the delegation of authority, and the encouragement of shared decision-making.