With the increase of the importance of the safety and environmental protection at sea, safety is a core design factor of maritime systems. Safety is defined as a perceived quality that determines to what extent the management, engineering and operation of a system is free of danger to life, property and the environment (Kuo 1998). There are many possible ways of dealing with the safety of ships. The rule-based approach is most commonly used in ship design. However there are many drawbacks to assure the safety objectives for a new ship and marine systems. This paper aims to investigate a systematic and rational approach to achieve the safety objectives of new ship in design process. Risk-based methodologies including the FSA (Formal Safety Assessment) and their applications to maritime systems are reviewed. Based on the principles of systems engineering and risk assessment, a process of safety assessment in ship design is established and proposed.