The thesis "Communication innovation on social networks: a case study of Elon Musk and Tesla" investigates Elon Musk's communication on social networks and its connection to the Tesla brand. Social networks have enabled easy and fast communication between users, resulting in communication innovation which facilited their use for other purposes as well, namely promotion and self-promotion. Such innovation works well for the chief and executive director of Tesla, Elon Musk, who uses social networks, mostly his Twitter account, to communicate in an innovative and authentic way. In addition to sharing his business goals and information about his companies and products, he also talks about his personal life and shares thoughts that are unrelated to his work. He also interacts with users to large extent, which creates a strong bond between him and his followers who can in turn potentially spread his news further and thus promote Tesla. The thesis defines the communication innovation and its use in authentic communication providing the example of Elon Musk and Tesla. It analyses previous research on Tesla's marketing strategies and shows Elon Musk's ability to influence the stock market and cryptocurrencies with his posts, which often appear in the media as a main or secondary theme. In addition, the thesis investigates social networks use in Croatia and the social media behaviour of Elon Musk's and Tesla's Croatian followers. It further illustrates the way in which they attain the information regarding Elon Musk and Tesla and the extent to which they are informed about his posts and news in general.