After integrating international aviation into EUETS，EU prepares to fake similar measure emissions from international shipping. However to hackle it may be an extraterritorial jurisdiction if EU marine ETS fakes similar way as it did in international aviation and covers the whole voyages from non-EU vessels that lake place beyond EU territory in conformity with international law. Ahhough It is permissive for EU marine ETS to expend ids porgy slake jurisdiction beyond EU's jurisdictional sea areas in accordance with international law of the sea to some extent， ids legality depends on what enforcement measures it lake to foreign vessels' entering into EU ports when violation of EU marine ETS happens. The EU marine ETS is a newly-appeared unilateralism. As a resuh，China should pay immediate attention to it and assess ids potential impact on China in advance.