The forth plenary session of the 18th Communist Party of China（CPC）Central Committee announced “comprehensively advancing the rule of law”.This requires promotion of marine management with the law as well as strengthening marine construction under the law.Marine legislation，marine enforcement and marine ecological civilization reflect in marine management under the law. In order to realise marine management under the law，a “Five in One” national marine manegement system which is systematic scientific，legally valid needs to be established and improved.