This paper is intended as an investigation of introduction of Maritime Security System. In the last few years, several articles have been devoted to the study of ISPS Code(International Code for the Security of Ships and of Port Facilities). The Diplomatic Conference on Maritime Security held in London in December 2002 adopted new provisions in the International Convention for the Safety of Life at Sea, 1974 and this ISPS Code to enhance maritime security. These new requirements form the international framework through which ships and port facilities can co-operate to detect and deter acts which threaten security in the maritime transport sector. Accordingly, the purpose of this paper is to suggest an introduction, if Maritime Security System and understanding of ISPS Code.