Underwater security in ports is an increasingly important topic of maritime security. The aim of this research was to analyze various aspects related to underwater safety, including types of threats, legal regulation, technical protection, forensic analysis and prevention. This research evaluates the different types of threats that occur to national security and the measures that are implemented to prevent such incidents from occurring. In order to conduct this research, various sources of information were used, including academic literature, legal regulations and expert opinions. Results indicate that underwater security in ports is extremely important and a critical aspect of national security. Legal regulations and technical protection measures that are in force have proven to be effective in preventing incidents, but there is still room for improvement. Also that effective underwater safety requires a combination of legal regulations, technical protection and well-trained personnel. The findings suggest that there is a need for greater awareness and understanding of underwater security in ports, and that existing systems and processes need to be improved. In the event of an incident, it is critical to have a well-established process for conducting a thorough forensic analysis to determine the cause and extent of the damage. This information can then be used to improve security measures and prevent similar incidents in the future. Also the importance of conducting regular assessments of existing technical protection systems and adjustments as needed. This includes the need for periodic updates of the underwater safety infrastructure and the implementation of new technologies, as well as for regular training of personnel. The conclusions of this study suggest that there is a need for further research and development in the field of underwater security in ports, with a focus on the development and implementation of best practices and standard operating procedures. This includes the need for more effective and efficient technical protection systems, the establishment of clear legal frameworks and regulations, and the improvement of forensic analysis and incident mitigation processes. In conclusion, this research highlights the importance of a multi-pronged approach to underwater security in ports as a segment of national security, including law enforcement, technical protection and adequate training of personnel.