This study examines the criticisms of the religious radical thought that emerged in the Islamic world after the sixties as an anomaly of the mainstream Islamism and the Islamic movement, directed against mainstream Islamism and Islamists, especially the Ikhwan-i Muslimin. The fact that both schools of thought react to the problems concerning the Islamic world and Muslim society with theo-political sensitivity, causes these two schools to be included in the same category under the definition of "political Islam" from time to time. The main objective of this article is to try to demonstrate that both schools are in complete opposition on many issues through the criticisms of the jihadi salafi ideologues like Omar Abdurrahman, Ayman al-Zavahiri, Abu Muhammed al-Makdîsî, Abu Musab al-Surî and Abu Yahya al-Libi against mainstream Islamists by examining the primary texts of religious radicalism. In this study, these criticisms are examined under three main headings: "In the Context of the Relationship between Religion and Politics", "In the Context of the Relationship between Religion and Law" and "In the Context of the Problem of Islamization Method and the Relationship with the Other".