The influence of religion on politics is inherent not only to the Islamic world, however, none of political theorist should ignore the role of Islam in Muslims’ public life, its impact on the policies of Muslim nations and the global geopolitical situation. Due to its historical uniqueness Modern Islam is not only a religion but also a way of life for the vast majority of Muslims and the basis of their civilizational and even national self-identification. Therefore, the role of religion in the Muslim world is different to that of countries, mostly populated by Christians, as Christianity is legally separated from the system of public administration in European countries. Islam, on the other hand, regulates not only the sociocultural sphere of society, including human relations, but also significantly affects the socio-political life of many Muslim countries, where Islamist movements have now become the major part this sphere.In Egypt, where authoritarian secular regime of Hosni Mubarak was overthrown during the revolution, Islamists took the lead in the protest movement, won the first democratic elections and used the opportunity to lead the country after nearly 60 years of underground activity. This paper examines the influence of the religious factor on the change of Egypt’s political regime in 2011-2013 by conceptualizing the terms of “political Islam” and “Islamic fundamentalism.” The author concludes that the Egyptian Muslim Brotherhood and its Freedom and Justice Party should not be defined as “fundamentalists” because: 1. they don’t try to return to a “righteous caliphate,” Sharia, and a literal perception of the sacred texts; 2. the Brothers could not be viewed as the most conservative force among Islamists, while Salafists are properly rightly considered to be; 3. the association is considered as a part of moderate Islamism, an ideology that does not mandate any the use of armed methods of struggle. At the same time, the author argues that owing to the fact that Egyptian “Muslim Brotherhood” adhered to moderate Islamism as an ideological party basis, it became a decisive reason that provided them a venue at the top tier of the government in 2011-2013.