Significant contributions in the extant literature emphasize green human resource management’s critical role in driving organizational success and enhancing its competitive advantage in the market. While previous studies have highlighted the positive relationship between green human resource management and green performance, there is a paucity of research on its influence in building a green competitive advantage. This chapter provides a systematic literature review aiming to address this gap by investigating the impact of green human resource management on firms’ green competitive advantage across diverse industry sectors, exploring the mediating role of external stakeholder involvement. The chapter highlights key outcomes of green human resource management practices, including enhanced employee morale, engagement, and productivity; improved recruitment and retention; increased cost savings; more substantial brand recognition and customer loyalty; and better regulatory compliance. By offering a systematic analysis of these dynamics, this chapter provides valuable insights into how green human resource management can serve as a strategic driver for achieving sustainable competitive advantage.