The role of the Internet and social media in everyday life has become extremely important in recent years. Thanks to the openness of communication, the easiness of connectivity and the possibility of active participation, Internet has become one of the most powerful media. It has also gained its role in the field of promotion.That is recognized by more and more businesses on a daily base, especially in the field of tourism, primarily because of direct communication with clients. The aim of this thesis is to analyze the online communication of the Croatian National Tourist Board on social media Facebook, Instagram and Twitter. With quantitative methods this thesis analyze the current themes communicated by Croatian National Tourist Board, interaction of posts and frequency of communication in preseason, season and postseason on its social media. The analysis has shown that the nature is the leading theme in the all analyzed posts. The main focus of the posts and the interaction is not sufficiently represented. Therefor, analyzing activity on social media over the analyzed periods, the largest activity was recorded in the preseason, but neither the season nor the season did not deviate to a greater extent. The research concludes that the Croatian National Tourist Board has recognized the importance and the role of social media in promoting Croatia as a desirable destination.