Abstract:The electricity ancillary service market is the foundation to ensure the safe, stable and efficient operation of new power system. The electricity ancillary service market in China develops organically, where the product are enriched, the fee compensation mechanism is optimized, and the market clearing regulations are gradually improved. However, the electricity ancillary service market in Sichuan is relatively lagging behind, which exists the problems such as limited number of products and market entities with low market maturity. Through the systematical summary of development process and experiences, and based on the resource endowment and power grid characteristics in Sichuan, the construction of electricity ancillary service market is analyzed. Suggestions such as enriching the types of ancillary service, developing new market entities, improving compensation mechanism, and completing market framework are proposed, which can provide support for the construction of electricity ancillary service market in Sichuan.