With the proportion increase of renewable energy in the power system, the fluctuation, randomness and intermittency of its power generation output will bring greater operating pressure to the power system. Hence, the power system needs to have a certain flexible adjustment and response ability to deal with the potential situations of wind, light and load loss caused by intermittent renewable energy, which has higher requirements for system flexibility. At present, China has not systematically carried out research on the market mechanism to improve the flexibility of power system,and there is still a large degree of imbalance between the supply and demand of power system flexibility. Considering the current situation that China’s power system flexibility needs to be improved,model first summarizes and analyses the market mechanism construction experience and research status of the United States and British on improving power system flexibility, and then analyzes the progress and challenges of China’s power system flexibility construction. Finally, putting forward relevant suggestions to promote the improvement of China’s power system flexibility.