The paper explains the issue of establishing a maritime domain cadastre and the importance of establishing the boundaries of maritime domain. Particular importance is given to the clear definition of the concept of maritime domain in order to make it clear what area can be declared a maritime domain and why and what is its spatial coverage. Legislation has tried to establish a maritime cadastre as a separate part of the cadastre, but it has not yet been achieved. Today, the maritime domain and its boundaries are entered in the land registers kept by the municipal courts. The authors consider it important to initiate the process of revision of Maritime Domain and Seaports Act (hereinafter: MDSA), adopted in 2003, which has changed several times, but without resolving the open issues of maritime domain management. This is especially important in order to avoid the misuse and misappropriation of maritime domain and to harmonize the activities of coastal counties in the process of establishing the boundaries of maritime domain.