Sovereignty in Islam means hakemia in Arabic and it is related to a holder of supreme power in a society, called hakem. In Islamic political and legal theory, a holder of sovereignty is God. God is a holder of supreme power, and above all, a legislator. Thus, in Islamic countries, a secular concept of a state regulation and having nation as a holder of sovereignty, man's rights and freedom of political organization is unacceptable. Moreover, when there is such a regulation in legal and political acts, it contains the previous fact that the sovereignty holder is God, and a nation's sovereignty is limited. Despite numerous changes that have happened in Islamic world during history, this view and understanding of sovereignty has not changed. Until recently, Islamic countries have not had any laws except those regulated by religious authorities. Even when the leaders used their power to proclaim regulations of a laic character, they had to give religious legitimacy to those regulations, and God has been and still is the only holder of sovereignty. Having showed how traditional Islam has treated sovereignty, the aim of the authors is to show how it is treated today. In fact, the autors' intention is to examine whether the idea of God's sovereignty is still present. As previously said, in essence, nothing has changed. Or more precisely, the theory on God as an exclusive sovereignty holder has not changed in almost the entire Islamic world. However, something else has been done, and it is contained in the fact that this view has been wrapped in contemporariness. The paper analyses the issue of sovereignty in Islam through two approaches: the first approach represents a thesis on unity of religion and politics in Islam, while the second one deals with the analyses of political praxis of Islamic states. On the basis of the analyses of Constitutional texts and practice, it is possible to divide Islamic states into three groups. The first group is the one where, by the Constitution, is clearly determined that God is a sovereignty holder; the second one, where a nation or a state has been determined as sovereignty, either as independent holders of sovereignty or in a community with its leader. The third group of states is the one that determines its sovereignty and holder in a similar way as it has been done in Europe and America. According to the Constitutional provision of these states on Islam as a state religion, conclusions on sovereignty of nations and borders have been drawn.