The number and the political programs of Algerian Islamic parties have significantly evolved since the genesis of Islamic parties between 1989 and 1992. This period, corresponding to the first attempt of democratization (after 25 years of one party rule, FLN), was stopped brutally with the cancellation of the legislative elections won by an Islamic party, the Islamic Front of Salvation (in French, FIS). The military, backed by the government and part of the civil society, decided to cancel it, with the rationale that the FIS constituted a threat to the durability of the democratization, due to the violence and acts of intolerance of a certain number of its members and elected representatives, and to the vehemence of its leaders’ declarations. In short, the FIS was accused of using democracy to destroy democracy. Subsequently, Algeria experienced a decade of violence and instability, leading to 200,000 victims. From that period, the field of Islamist parties has considerably changed. This evolution is characterized by three elements. First, we notice a pluralization of Islamic political parties: from three parties in 1989-90 to eight parties in 2018. Second, we notice several changes of these parties’ names: during the period of democratization (1988-1992), the political identity refereed explicitly to Islam, particularly regarding to the name and acronym of the parties: Islamic Front of Salvation; Ennahda (Movement of Islamic Renaissance); Hamas (Movement of Islamic Society). In the second period, after the adoption of a new constitution (1996) and the resumption of the electoral process (from 1997), we notice a transformation of their political identity. The type of denomination has changed considerably, without any explicit reference to Islam. Third, we notice an evolution of the political program: they refer to Islam, but this reference is not exclusive anymore, as it was the case before 1997. How can we explain this evolution? The aim of this contribution is to address a paradox. From the resumption of the electoral process, the government hardened the conditions regarding the legalization of political parties by a restriction of their religious basis. Paradoxically, this restriction resulted in the pluralization of Islamic parties. We propose a three-stage analysis. Firstly, we will describe the characteristic of the evolution of Islamic parties. Secondly, we will examine the legal conditions structuring the party system, particularly the criteria regarding the place of religion when legalizing new political parties. The third section will be devoted to the presentation of our hypothesis designed to explain the pluralization and the euphemization of the Islamic parties. Our approach is based on a critical reading of the literature on the birth of political parties.