This book presents a comprehensive account of China's evolving international energy relations (IER) as the world's largest energy user transitions from fossil fuels to renewables amidst significant geopolitical shifts. It introduces an original analytic framework for IER, focusing on three interconnected dimensions: the international business activities of energy companies at the micro level, state energy diplomacy and energy statecraft at the state level, and the nation's engagements with the global energy governance at the global level. Drawing an extensive range of Chinese and English-languages sources and employing novel perspectives, the book provides a timely analysis on this significant phenomenon. It constructs a compelling narrative on the profound impact of China's domestic energy transition and the changing geopolitical landscape on the country's international energy engagements.