Currently, China has become the world’s second-largest consumer market for cosmetics. The number of licensed cosmetic manufacturers nationwide is more than 5,400, with more than 87,000 cosmetic registration and records subjects of all kinds and nearly 1.6 million products effectively documented. Although domestic brands are on the rise, on the whole, it is still some international brands that occupy the largest share of the domestic cosmetic consumption market. The development of social media, especially social platforms such as RED, where beauty products are the main domain, provides a more efficient data collection platform for domestic beauty brands to penetrate deeper into the market. This paper conducts effective market segmentation in more comprehensive dimensions and develops differentiated positioning strategies. Taking the foundation market as an example, this paper uses RED as the main platform for data mining to provide a reference for the process and ideas for companies to use social media platforms for market segmentation. From the analysis results, the data from social media platforms go beyond the traditional method of market analysis by collecting demographic, geographic data, and so on, by directly segmenting according to consumers’ actively expressed demands, thus making the basis of market segmentation more accurate and refined. Furthermore, the social media platform can show the competition situation of each segmented market. The analysis of competitors’ related data provides a more accurate basis for market assessment and, ultimately, precise positioning.