Tourism as an industry is in a complex relationship to the issue of environmental sustainability and negative effects.The concept of sustainable development in tourism is importantbecause it takesinto account theeconomic, environmental and socio-cultural effects of tourism on thedestination. Eco-tourism has emerged in parallelwith the concept of sustainable tourism development. Tourist motivation of visitors refers to the needs and motives of tourists for travel. Modern tourist demand requires heterogeneity of products and services and a focus on creating visitor satisfaction. The strongest motivators in making the decision to visit the national park are new experiences. With the growing demand of the tourist market for cultural and eco-tourism destinations, Croatian national parks have the opportunity to position themselves on the international and domestic market in order to attract visitors motivated by staying in nature with an emphasis on sustainability. Tourism based on natural resources, eco tourism, is one of the tourism of special interests whose natural resources are also one of the main factors on which the motivation of tourists to visit a particular tourist destination is based. Therefore, the aimof this research was to examine themotivational factors of tourists when choosing the Brijuni National Park as a tourist destination and to discover the main motivating factors that attract tourists to the destination. Brijuni National Park has a long tradition of tourism development and many cultural, historical and natural attractions that can contribute to attracting tourists with special interests. The implementation of projects in the national park improves the natural heritage and manages it sustainably. The projects of the Brijuni National Park contribute to the restoration and preservation of cultural and historical heritage, its presentation and interpretation.