Today, it is increasingly difficult to stand out in a multitude of brands. In order for the brand to stand out, many brands resort to various forms of promotion. One of the most effective channels for promotion are social media networks. Social networks are a free channel for raising consumer awareness, but also relatively inexpensive for paid promotion compared to conventional advertising channels such as television etc.. Therefore, more and more brands are turning to social media networks to stand out in their own unique way. This thesis seeks to explore which social networks play in strengthening brand loyalty on selected examples, energy drink brands, Red Bull and Rockstar. Six social networks were analysed: Facebook, Instagram, YouTube, Twitter, LinkedIn and TikTok, respectively selected brands and their communication on social networks. The aim of the thesis is to determine the way consumers perceive selected brands on social networks. A survey of 185 respondents showed that almost all of them use social networks on a daily basis and spends an average of about 90 minutes on them. Thanks to the research and comparison of the two brands of energy drinks, we can see how much social networks influence the relationship between the brand and the customer and how much the brand profile on social networks instils trust in the customer when choosing products or services.