Abstract: Decarbonization of power sector is critical for the emission reduction target of Paris Agreement targets. However,it also faces enormous difficulties and challenges,with strong complexity and uncertainty. In order to explore feasible and affordable decarbonization pathways of China's power sector,a bottom-up energy system model with high spatiotemporal resolution and technical accuracy was built to simulate and optimize the development pathways. Three typical scenarios( Business as usual scenario,2 ℃ scenario and 1.5 ℃ scenario)were set to analyze the decarbonization pathways and the corresponding implementation plan. The results indicate that the 2 ℃/1.5 ℃ targets stipulated in Paris Agreement cannot be realized based on the current development trend,which can only be achieved with faster expansion of renewable energy,quicker phase-out of coal-fired power plants as well as the large-scale deployment of carbon capture technologies. In the next 30 years,wind and solar power should gradually become the majority of power supply. The annual incremental installed capacity should reach 2-4 times of the current level. The capacity of coal-fired power plants needs to shrink gradually and some of them even need to be prematurely decommissioned,which will reduce the average lifetime of coal-fired units by 0.42 to 1.93 years,translating to the stranded cost of 105 billion to 655 billion yuan. Carbon capture technologies need to be largely deployed,especially the coal-biomass co-firing power plants with carbon capture devices. By 2050,the annual captured carbon dioxide should reach 0.89 Gt to 1.08 Gt. In order to guarantee the low-carbon transition progress,some important issues should be dealt with,including power grid security and stability,orderly coal power phase-out,the deployment of carbon capture technologies and transition cost. These issues could be effectively solved by enhancing the research and development of advanced technologies such as energy storage,establishing an orderly phase-out mechanism for coal-fired power plants,accelerating the demonstration of carbon capture and storage technologies and establishing the green investment and financing mechanism. Tackling climate change is the common responsibility of all mankind. Measures and policies should be deployed ahead of time from now on so as to achieve the decarbonization of China's power sector under the 2 ℃/1.5 ℃ targets.