Abstract: In recent years, with the gradual improvement of China's electricity spot markets and carbon markets, how to better achieve the deep coupling between the two markets and promote the development of the electricity-carbon market towards a competitive market has be-come a new research focus. This paper proposes a multi-stage optimization model for the electricity spot market clearing considering the carbon trading and studies the equilibrium problem in the electricity spot market under this model. In the first stage of the proposed model, a carbon quota allocation model for the market units is established. In the second stage, a tiered carbon trading mechanism is introduced, and an electricity spot market clearing model considering the minimum cost of both the electricity quantity and the tiered carbon trading is established based on the carbon quota of each unit. In the third stage, an electricity price tracking model with the mini-mum energy cost and a unit carbon cost calculation model are established based on the carbon quota and the bid information determined in the first two stages. Finally, the proposed model is implemented on the improved PJM5 node system (Pennsylvania-New Jersey-Maryland 5-bus power grid), and the validity of the model is verified from the aspects of the clearing result and the market equilibrium result. The results show that the proposed model is able to balance the economic and low-carbon goals of the market clearing, maximize the carbon emissions reduction without increasing the total cost of the electricity-carbon coupling. Meanwhile the user-side electricity cost is reduced by enhancing the subjective initiative of the power generation units' participation in the market competition.