Today, there have been many changes in the way of transition from traditional media to social media, as well as changes in purchasing behavior. The growing popularity of social media platforms in the daylight becomes a medium in which consumers are researching the products and services they will buy, as well as the use of such things as research, communication, fun, learning new things, sharing. As social media play an active role in our lives, there are changes our in consumer buying cycles. Consumers appear to be affected by factors such as user comments on social media, content created by other consumers, reference groups, family, environment in the procurement decision process ate. After the purchase, the product can freely share any kind of thought about the service without space and time constraints. The active social media platform has become a center of attraction in terms of brands and companies. This research was conducted to determine the effectiveness of social media on the purchasing behaviors of the Y-branch, which is dominated by social media and lives with technology. Findings obtained; Y-generation consumers are allocating a significant amount of time to social media and are researching the products / services they will buy by connecting to social media from their mobile devices. Consumers of Y generation show that they are positively affected by comments and sharing in the social media environment when purchasing products / services.