Social networks have fundamentally changed the way we communicate and made it accessible to all people around the world. In addition to communication, social networks have influenced many other aspects of people's lives, including shopping behavior. "The influence of social networks on the decisions and behavior of young consumers" is the topic of this thesis. The paper is divided into theoretical and research part. The theoretical part consists of secondary data that provided insight into the theoretical aspects and basic features of social networks, internet marketing and consumer behavior. Using a survey questionnaire that is a research part of this paper, we tried to reveal the attitudes and habits of young consumers (up to 28 years). Specifically, the research sought to determine how the use of the social network Instagram influences the decision to purchase a product or use the service among young consumers. After analyzing the results of the survey questionnaire, the conclusion of the entire research was made and proposals for companies were given, while at the very end there is a conclusion of the whole paper.