With electricity marketization for over 20 years, United Kingdom (UK) has established a relatively complete electricity market system. However, owing to global climate change and environmental factors, the UK third electricity market reform attempts to ensure that the future electricity supply is secure, low-carbon while affordable. According to documents released by the UK government in recent years, this paper summarizes and gives an account of the main contents of the UK electricity market reform, including feed-in tariff with contracts for difference in price, emissions performance standards, capacity market and carbon price floor, regulatory asset base and others, and a brief discussion of the expected results. Finally, the enlightenment significance to China's power market construction is described.