This study analyzes the compatibility of Shariah with International Law on freedom of religion. As a subject of colossal complexity and variation, detailed examination is restricted to the highly contentious issues of the right to change religion (otherwise termed apostasy in Islamic law), the religious rights of non-Muslims (Dhimma) in an Islamic State, relations of law and religion (state religion), blasphemy/defamation of religion, and the application of the doctrine of jihad in defence of the Islamic faith, etc. Today, the serious disregard and infringement of freedom of religion by both State and non-State actors has kindled hatred and caused violence among people, as evidenced by severe and systematic persecution, domination and suppression by one religion or sect over the other using the instrumentality of State power in many countries across the globe. Many instances abound on the oppressive treatment and discrimination of members of minority religion or faith within a nation; arbitrary killing and violence to the life and properties of the holders of certain beliefs or sects; willful destruction of or damage to places of worship and other sacred sites of cultural and religious memory and learning in many parts of the world. In view of this, the main objective of this work therefore, is to examine what comparable or divergent visions and precepts underlie Shari‟ah law and international law in providing for freedom of religion given the fact that as to Shariah, preserving the Islamic faith is among its fundamental principles and as to international law, promotion of tolerance and friendly relations forms its very basis. To achieve this, doctrinal method of legal research was adopted, and reliance was placed on sources of information such as the primary and secondary sources of Islamic law as well as the sources of international law on the subject. It is argued that while international law contemplate protection of freedom of religion only of recent, the Shariah as a system of law and religion was the first to recognize religious toleration right from the 7th Century A.D. and in view of this, it was observed that religious accommodation in Islamic tradition is only tenable under Islamic Rule than in democracy, socialism or communism, therefore a return to Islamic Khilafah system was advocated. It was further submitted that freedom of religion in its international law conception is far from being universal and remain the most contested freedom in view of its failure to recognize other legal and cultural traditions, the Shariah in particular. The findings reveal that rules of international law related to freedom of religion are to a large extent, contradictory to those found under the Shari‟ah, it being the formulations of international standards remain largely reminiscent of Western as well as Judeo-Christian traditions to the exclusion of Islamic particularities. Consequently, much of the current legal problems associated with violations of freedom of religion in Western countries as well as by Muslim majority countries are argued as being partly due to the existent doctrinal incongruence between the two systems of laws. The study concludes with the view that attainment of “universal” standards on protection of freedom of religion is possible, only if the international community appraises itself of the relevance of Shariah within international human rights discourse as an alternative legal tradition.