The development of geo-engineering applied to the oceans-ocean fertilization, trapping and geological storage of CO2-has put two areas of international environmental law in tension: climate law and international law of the marine environment. This study aims to think about the role that the international environmental law could or should play toward the development of the geo-engineering. The discussions on geo-engineering that have taken place in international fora are rich in lessons about these rights themselves, with regard to their effectiveness and efficiency, but also to their articulation, and they allow to understand the position of the different organizations a front of these new techniques. Thus, the question of the " good governance" of this new challenge raises. It is therefore a question of presenting the various possibilities offered by international law to frame-even forbid-these new practices.