Small Modular Reactors (SMRs) represent a new generation of reactors characterized by plants with a reduced power output and modular design. Their aim is to improve safety, flexibility, and economic feasibility compared to conventional large reactors. These features make SMRs promising candidates for the decarbonization of many fields of energy production, including innovative applications such as in the marine environment. This work investigates the use of SMRs for the propulsion of large commercial vessels such as container and cruise ships, and also for offshore applications for the powering of coastal areas. However, the integration of nuclear reactors in marine environments raises specific technical and safety challenges that require dedicated analysis.