Abstract-The study investigates into the fast fashion industry worldwide, specifically on Zara, H&M and UNIQLO with respect to efficient supply chain management, scarce value creation, low costs promotions and positioning strategy, supported by comparisons between several typical well-known fast fashion brands. Through the overall analysis of B2C apparel online retailing in China, statistics show an enormous space for online retailing fast fashion industry to explore but a far way to catch up with the leading enterprises in the world in terms of e-commerce scale. The next main part demonstrates a case of a Chinese fast fashion online retailer-Vancl, analyzing its keys to success in aspects of proper product positioning, brand positioning, business mode, marketing strategy, products and services, user experience, logistics and team management. In addition, relevant suggestions for further prosperity are proposed in the end of the paper.Index Terms-fast fashion industry, e-commerce, B2C, online retailing