When economic sanctions are unilateral there is a higher possibility that that these are not legal legitimacy into question. It will be analyzed in this paper, on international economic sanctions in the context of globalization and the political crisis among the several States, the application of these, in most cases it has adverse consequences for development international. From the foregoing it has become necessary, on the one hand, the creation of institutions of international scope that lessen the harmful effects of the crisis and on the other hand, the imposition of various sanctions to mitigate and penalize states that violate International Economic Law. In principle the notion of international economic Illicit be analyzed, their deeds generators, their different classes and possible consequences. Given the effects caused by the different economic transgressions, it arises the responsibility for the offending State and as a result some sanctions will be imposed to counter the assault on law International. In the development of this writing, it will emphasize the distinction arises between the economic sanctions legal and illegal character based on the idea that the first to be supported by multilateral organizations are considered at a higher degree of legality, whereas the latter being imposed unilaterally tend to be illegal, despite its unilateralism it does not mean that in certain cases can be legal. It deepened about the role that the active agent, such as Organization United Nations (ONU), the World Trade Organization (OMC), the European Union and the Organization of American States (OEA) in various international cases where glimpse and appreciate the direct and indirect consequences, both positive and negative within the International Economic Law. To end the case study of Ukraine - Russia and Cuba to analyze the effects obtained as a result of economic sanctions imposed on States thatwere participants in these conflicts.