The topic of this thesis is SEO optimization of business websites. SEO (Search Engine Optimization) represents a set of rules that webiste authors follow with the aim of better positioning in search results on today's Internet search engines. The importance of webiste optimization is seen in the fact that more and more companies are trying to switch to an online way of doing business. The goal of the company becomes to attract as many visitors as possible who will be interested in certain services or products that the company offers and ultimately lead to the desired action, i.e. a visi tor a sale. Therefore SEO, as such, is a key aspect of any successful digital strategy. Social networks, as well as various other communication channels, can be a very good way to promote a certain service or product, but in most cases, SEO optimization gives much better and more lasting results. The paper contains a theoretical presentation of the concept of website optimization and its importance. Terms such as white hat SEO and black hat SEO, On-page and Off-page SEO, Internet search engines, the influence of social networks, SEO trends and popular SEO tools are explained in more detail in the paper. In addition to the theoretical presentation of the aformentioned concepts, the paper also contains a practical example of optimizing a business website, where the steps and results of the optimization are described. According to all the above, the purpose of this pape is to point out the importance and complexity of SEO optimization of business websites.