This thesis aims to investigate the topic of green hydrogen production through the electrolysis reaction from desalinated saltwater to analyze the current technical and economic issues. First, a general overview of the electrolyzers currently available on the market and under development is given, which reveals that the best option for hydrogen production at sea are alkaline electrolyzers, as they represent the cheapest and most efficient technology in this field. Furthermore, it is shown that it is possible to produce the electrolyte on-site through the Chloralkali process, avoiding the risks and costs of its manual replacement. Then, the advantages and disadvantages of hydrogen production at sea are highlighted, pointing out that the use of saltwater for hydrogen production will be crucial in the future to avoid problems of freshwater scarcity and environmental impact.