In this diploma paper entitled Boat Marathon as Intangible Cultural Treasure the Boat Marathon is represented as anevent of great significance for the Neretva Valley. Terms related to intangible cultural heritage are analysed, as well as all conditions that need to be fulfilled in order for an event to become a cultural treasure.Boat Marathon as a potential intangible cultural treasure is analysed in the paper together with criteria that the Marathon ought to meet in order to become one. This imposes the question whether the Marathon participants would want the Marathon to become cultural treasure, or the goal is somewhat different. Also, questions related to participants, issues, policy and heritage are being answered. Furthermore, changes that occurred in the Marathon throughout the course of time and their causes are being analysed. The question that imposes is the preservation of this event, so it is of great importance to examine in what way the Marathon is being protected.