The work aims to study the influencing factors of fashion brand values under the dual-carbon background, with a particular focus on the relationship between low-carbon marketing, low-carbon brand image, and consumer purchase intention. Firstly, the challenges faced by fashion brands in the textile and apparel industry in terms of carbon footprint were identified and analyzed with reasons in three stages:raw material procurement, production, and product sales. Secondly, based on the relationship between these challenges and the factors of low-carbon marketing, low-carbon brand image, and consumer purchase intention, a model of influencing factors on fashion brand value under the dual-carbon background was constructed, and research hypotheses were proposed. Finally, factor analysis, correlation analysis, and regression analysis were employed to verify the relationship between variables and test the mediating effects. The results indicated that low-carbon marketing had a positive impact on the formation of low-carbon brand image. Both low-carbon marketing and low-carbon brand image had a positive influence on the brand value. Consumers' purchase intention partially mediated the impact of low-carbon marketing and low-carbon brand image on the brand value. In conclusion, the primary factors influencing the fashion brand value include the brand's low-carbon marketing strategy and the establishment of a low-carbon brand image. To achieve sustainable development goals, fashion brands need to adopt low-carbon measures in raw material procurement, production, and product sales, actively implement low-carbon marketing strategies, and shape a brand image with low-carbon characteristics in order to enhance the brand value. Although this research focuses on textile and apparel products within the fashion brand context, the findings can also be applied to a certain extent to luxury brands, lifestyle brands, and their respective product domains.