The objective of this study is to investigate the impact of delegation of authority (DA) and transformational leadership (TL) on individual performance (IP) through the mediating role of individual adaptability (IA) at PLN Indonesia power, a subsidiary of the state-owned company PT.PLN. As a power plant operator and energy solution developer, Pt.PLN Indonesia power is facing multiple challenges due to rapidly evolving business environment. External challenges are arising from various sources, including the global target of the PLN group to accelerate the adoption of renewable energy, changes in the supplier structure due to the entry of private and public sectors into the electricity supply industry, and the demand for advanced technologies to enhance power supply and distribution efficiency. Internally, the company is facing a significant decline in market share, falling from 48.92% in 2003 to 19.1% in 2021, according to the annual report to PLN Indonesia power. To analyze the data in this research, descriptive and inferential statistical analyses were conducted using SPSS and SmartPLS 4 software. The study's results indicate a statistically significant positive impact of delegation of authority and transformational leadership on individual adaptability, and of transformational leadership and individual adaptability on individual performance. Furthermore, individual adaptability plays a positive significant ,ediating role between delegation of authority and transformational leadership on individual performance at PLN Indonesia power. This study recommends that organizations invest in leaders who communicate a clear and positive vision of the future, encourage innovative problem solving approaches, and foster trust, involvement, and cooperation among team members. Additionally, organizations should prioritize developing individual adaptability and delegation of authority to enhance their market share, the reliability of the electricity supply, and to develop renewable energy sources to meet the Indonesian people's electricity needs.