Abstract: The clearing results of the electricity spot market are influenced by market participants' bids and various coupling constraints. Quantitative analysis of the factors influencing the clearing results is beneficial for market operators to gain a deeper understanding of the causes of market operation results, thereby enhancing the organizational safeguarding capabilities and market risk prevention capabilities of spot trading. To this end, this paper proposes a quantitative characterization of the factors influencing market clearing results and a market power evaluation method. Firstly, a model for the participation of consumers in the electricity spot market clearing is established, and a method for quantitatively characterizing the market clearing results is proposed. The impacts of generator characteristics, line transmission capacity, and load characteristics on nodal marginal prices and unit output are quantified, providing an analytical tool for analyzing the formation causes and influencing factors that influence electricity spot market clearing results. Based on this, a market power evaluation method is proposed to assist market participants in evaluating the effects of generator and load bids on profits. Finally, through case studies, the effectiveness of the proposed quantification method for factors influencing clearing results is validated, and the impact of changes in market members' bids on their own and other market members' profits is analyzed using the market power evaluation method.