Employee loyalty is a strategic organizational behavior construct that reflects employees’ willingness to remain with an organization, support its goals, advocate for it, and contribute beyond minimum contractual obligations. In an era of talent mobility, hybrid work, rising employee expectations, and competition for skilled labor, understanding the determinants of employee loyalty is important for human resource management and organizational sustainability. This article reviews the literature on determinants of employee loyalty using a structured narrative review. The review synthesizes conceptual, meta-analytic, systematic, and empirical studies related to job satisfaction, organizational commitment, perceived organizational support, employee engagement, compensation, career development, leadership, organizational justice, work environment, work-life balance, trust, psychological contract, and job embeddedness. The review indicates that employee loyalty is shaped by a combination of economic, relational, psychological, and organizational factors. Job satisfaction and affective commitment are central attitudinal foundations, while perceived organizational support, justice, leadership quality, and career development create conditions that strengthen employees’ intention to stay. Employee engagement, trust, and job embeddedness function as important mediating mechanisms. The article proposes an integrative conceptual framework linking organizational determinants, relational determinants, psychological mediators, employee loyalty, and organizational outcomes. This review contributes by organizing fragmented loyalty determinants into a coherent model and by proposing future research directions for empirical studies, particularly in service, education, and emerging market contexts.