This study examines the effects of school principals’ growth mindset and emotional intelligence on decision-making and their implications for elementary school climate. A quantitative survey involved 297 civil-service teachers, comprising 208 Government Employees with Work Agreements (PPPK) and 89 Civil Servants (PNS), from public elementary schools in Region I of Sumedang Regency, Indonesia. Respondents were selected through non-probability quota sampling. Data were collected using five-point Likert-scale questionnaires measuring growth mindset, emotional intelligence, decision-making, and school climate and analyzed using Partial Least Squares Structural Equation Modeling (PLS-SEM) with SmartPLS. The measurement model showed satisfactory reliability and validity, with Cronbach’s alpha of 0.753–0.862, AVE of 0.591–0.759, and composite reliability of 0.831–0.907. Growth mindset significantly and positively affected decision-making (β = 0.189, t = 3.247, p = 0.001), as did emotional intelligence (β = 0.761, t = 13.245, p < 0.001). Decision-making strongly and significantly influenced school climate (β = 0.917, t = 60.677, p < 0.001) and mediated the effects of growth mindset and emotional intelligence on school climate. The model explained 87.3% of decision-making and 84.1% of school climate variance. These findings underscore the importance of strengthening principals’ psychological capacities to support effective leadership and a positive school climate.