The goal of the research is the development of an autonomous SWATH vessel (Small-Waterplane Area Twin Hull) for various applications such as sea and underwater research, sea and coastal surveillance, communications, support to other ships and maritime systems, etc. To perform such diverse tasks, it is necessary to design a modular vessel to which individual modules can be changed and added depending on needs. The first version of the vessel with a module equipped with sensors for surveillance of the Adriatic Sea is planned. The number and type of sensors will depend on availability and capabilities. The load-bearing structure, underwater torpedoes and propulsion system will be fixed for all operational purposes. The power module and the payload module (sensors, equipment, etc.) will be upgradeable and interchangeable. The vessel will be powered by propellers driven by electric motors. A certain type of battery will be used as the energy source. The goal is for the vessel to be autonomous as long as possible in terms of energy, which will be achieved by installing a battery charging system at sea. The second part of autonomy refers to the independent movement of the vessel at sea and the change of location depending on the type of task that is currently being performed. Decisions about this will be made by the computer system installed on the vessel. The decision to change location depends on various parameters, from the response of measuring devices to moving to a safer area due to weather conditions or other hazards. The system will get part of this information from built-in sensors, and part in communication with the center, which will be able override the decisions of the internal computer system. The SWATH design will contribute to greater stability of the vessel and smaller motions on the waves, which is favorable from the point of view of the functioning of sensitive measuring, computer and communication equipment. In addition, this design reduces the need to change locations due to rough sea conditions. The project envisages dimensioning the hull and SWATH torpedoes in the underwater part to withstand wave conditions on the Adriatic Sea.