This final paper, whose topic is the promotion of prominent fashion brands on social media, analyzes the influence of these platforms on the fashion industry. The paper begins with an overview of how social media affects business in general, with a special emphasis on promoting products and services through these channels. Emphasis is put on the business model on the social platform Instagram, which is among the most important platforms for fashion brands. The paper also deals with the development of social media and their growth in recent years, as well as their role in strengthening brand recognition on the market. This paper provides insight into existing research on the ways in which fast fashion and luxury brands use social media for promotion. For the purposes of this final paper, research was conducted. The research methodology involved content analysis on Instagram, using a questionnaire form for systematic data collection. The results of the research provided an insight into the fundamental similarities and differences in the promotion strategies between fast fashion and luxury brands. Fast fashion brands on social media emphasize accessibility, frequent promotions and quick reactions to trends. On the other hand, luxury brands focus on exclusivity, high quality and creating an aspirational image.