Abstract: With the implementation of China's marine strategy and the development of the marine economy and trade, marine crime is becoming more and more rampant. At present, China's criminal legal system related to marine crime is relatively weak. There are many reasons for it, but the most important is that our country lacks a reasonable system to attack marine crime. Therefore, it is necessary to construct an effective marine system to combat marine crime, In view of the particularity of the object of marine crime and its infringement of legal interests, the construction of China's anti-marine-crime system should be based on the dual model of "on the sea" and "inside the sea". We should add provisions on marine crimes in international treatiesto deal with marine crimes, establish separate sections of criminal law to crack down on crimes with "sea", so as to punish marine criminal activities, protect marine environmental resources, and enable our country to fully fulfill her international responsibilities as a major maritime power.