Nautical tourism ports are a key element in the development of nautical tourism, as they offer sailors the opportunity to stay in a particular place, which points to the need to analyse them. In the paper, as an introduction to the elaboration of the topic, the theoretical determinants of nautical tourism ports are mentioned. At the same time, the concept and characteristics of nautical tourism ports, their classification and categorisation in accordance with the legal provisions in the Republic of Croatia are given. In this work, nautical tourism ports are understood as special ports used for receiving and accommodating vessels and equipped to provide services for users and vessels. The main focus today is on the analysis of the capacity and operation of nautical tourism ports in the Republic of Croatia. The capacity of ports for nautical tourism is monitored using quantitative data on the number of berths and the number of vessels, and compared with other EU Member States in order to make a statement about the level of development of reception capacity and the competitiveness of Croatian nautical tourism. In addition to the quantitative indicators of the development of nautical tourism ports in the Republic of Croatia, the services offered by nautical tourism ports and the business results of nautical tourism ports (revenues and expenses) are analysed. Based on the analysis and trends on the nautical tourism market, the tendencies of the future development of nautical tourism in the Republic of Croatia are examined. Emphasis is placed on the application of the principles of sustainable development as a compromise between the need to preserve natural space and the need for economic development, which implies the determination of the carrying capacity of space and the definition of the growth limit for new reception capacities.