Social media has become an important platform for influencing consumer behavior, and it is widely used for product promotion, brand marketing and consumer interaction. However, many differences between social media marketing and traditional marketing methods need to be studied and explored in depth. The purpose of this paper is to combine the Xiaohongshu marketing model with the SOR model and analyze the reasons influencing consumers’ purchase intention and their Xiaohongshu marketing through specific case studies to find the optimization solutions to help enterprises and brands improve the effectiveness of Xiaohongshu marketing. This paper first introduces the characteristics and modes of Xiaohongshu social media marketing, including UGC mode, KOL/KOC integration and grass-seeding marketing strategy. Then, through the SOR model, this study analyzes in detail the influence of stimulus factors such as content quality, KOL/KOC influence and user engagement and how they affect users’ purchase intention and decision-making. Finally, some suggestions are provided to improve the effectiveness of Xiaohongshu marketing, including improving content quality, choosing appropriate KOLs/KOCs, and promoting user engagement.