Abstract: Pumped storage plays a significant role in emission reduction for accomodating new energy and achieving clean replacement of peak shaving power sources. This paper describes the current situation of pumped storage participating in carbon quota trading market and voluntary emission reduction trading market, and analyzes the emission reduction mechanism of pumped storage in the process of reducing wind and photovoltaic curtailment and realizing clean replacement of peak-shaving power sources. Based on the Chinese certified emission reduction (CCER) methodology system, a pumped storage carbon emission reduction project scenario and calculation model is established, and the actual carbon emission reduction by typical pumped storage stations in 4 regions of China is calculated. The results show that the annual emission reduction by the pumped storage stations in East China, Central China and Northeast China is about 100,000 to 300,000 tons. Finally, the key factors affecting the carbon reduction effect of pumped storage are summarized as the proportion of thermal power in the region and the comprehensive efficiency of the pumped storage stations. This research can provide a reference for the development of CCER methodology for pumped storage and carbon emission reduction calculation.