This study explores the role of emotional intelligence (EI) in shaping leadership styles and executive functioning among Catholic higher secondary school principals in Kerala through a qualitative case study approach. Amid growing complexities in educational leadership, principals are expected to demonstrate not only managerial competence but also emotional and cognitive clarity. The study focuses on three principals selected from reputed Catholic institutions known for value-driven leadership and high community engagement. Using semi-structured interviews, institutional documents, and classroom observation reports, data were collected over a three-month period and analysed thematically. Findings revealed that high emotional intelligence facilitated adaptive leadership behaviours-ranging from transformational to servant leadership styles-which, in turn, enhanced the principals’ executive functioning capabilities such as decision-making, planning, stress management, and moral reasoning. The study affirms that EI operates as a foundational element influencing how leadership is enacted in emotionally complex and ethically charged school settings. The paper concludes with theoretical implications for educational leadership models and practical recommendations for leadership development in faith-based schools. By emphasising the interdependence of emotion, cognition, and action, this study contributes to the ongoing discourse on holistic school leadership.