The study of modern reservation systems was conducted to determine their role in the tourism industry and to improve understanding of the basics of marketing activities of tourism enterprises. The article aims to analyze the functioning of modern reservation systems in the market of tourist services, to structure the existing reservation systems according to the operation levels and according to the distribution channels of the tourist product. The main methods of scientific research were: chronological, systematic research, logical analysis, statistical and structural analysis, which made it possible to logically and systematically investigate the modern reservation systems of and determine their hierarchy. The result of the study was the substantiation and construction of a hierarchy of connections in the world market of tourist service reservation systems, based on the scale of coverage of the tourism sector and the distribution channels of tourist services. In total, there are 5 levels of travel reservation systems in the world. The authors came to the conclusion that modern reservation systems are a marketing tool for travel companies that contribute to the distribution and promotion of travel services