Due to the rapid development of Internet and technology, people rely on the internet more and more. The fast-paced evolution of technology has created new opportunities for marketers, with blogs being one of the newest phenomena. Brands invest in online marketing are increasing, so that inviting bloggers to write product endorsement advertising to create electronic word-of-mouth is one of current trends. As bloggers became the newest way of marketing in fashion industry, the researches about the impact of blog and bloggers to consumers become increasingly important. Therefore, this study was conducted for the fashion bloggers' endorsement advertisements, sorted out factors of endorsement advertisements, blog marketing and clothing evaluation criteria through literature analysis. Through in-depth interviews and expert multi-faceted amendment become AHP-based analysis questionnaire, to find out the important factors of product endorsement advertisements by fashion bloggers. Study found out that the 9 important factors of product endorsement advertisements by fashion bloggers are divided into blogger characteristics, blog characteristics, articles characteristics, consumer characteristics, product features, channel selection tendencies, brand image and social networking.