Environmental sustainability has gained significant importance for organizations, highlighting the crucial role of business leaders in addressing environmental degradation. However, the connection between chief executive officer (CEO) characteristics and environmental sustainability remains understudied in academic literature. Understanding this relationship is crucial, considering the significance of environmental sustainability in organizational strategies. This paper presents the first systematic literature review (SLR) on this topic, aiming to identify gaps and opportunities for future research. The SLR analysed 139 studies on the CEO–environmental sustainability relationship. The findings indicate a recent increase in research activity, particularly peaking in 2022 and focusing on China and the United States. Most studies employed upper echelons theory and examined the influence of CEO demographic characteristics on environmental performance. However, less attention has been given to CEO psychological traits, such as personality and ethical leadership, and environmental disclosure. Furthermore, qualitative aspects of environmental disclosure, including reporting tone, readability and specificity, have received less attention. The findings offer valuable insights for academics, practitioners and policymakers. Recommendations for future research include exploring the impact of CEO psychological traits and environmental disclosure on a firm's environmental sustainability. Additionally, studying cross‐country and cross‐industry differences in this relationship is encouraged. This study makes a significant contribution to the field by shedding light on the crucial and relevant topic of environmental sustainability and its association with CEO characteristics, providing valuable insights to guide future research and inform decision‐makers.