After the Islamic awakening in Tunisia, the collapse of the dictatorship of Zine El Abidine Ben Ali, the President of this country and the formation of a democratic and parliamentary political system, the two influential political factions in this country began to cooperate and converge with each other. The Ennahda movement, as the most important political trend in Tunisia, played a decisive role in political developments and other parties, including secular parties, welcomed the formation of a coalition government with the Ennahda. The participation of Islamists with the opposition (secular) parties in Tunisia and the formation of coalition governments was successful at first, but with the intensification of the differences between the two political factions, did not continue and reached a dead end. In this research work, the reasons for persuading Islamists and secular parties to form a coalition government and then refusing to do so are investigated. The question of the article is what were the grounds of the initial political alliance between Islamists and secularists after the Islamic awakening in Tunisia and why did this alliance collapse? The hypothesis of this research shows that "Al-Ghannoushi and the leaders of the Ennahda movement towards moderate Islam and democracy made it possible to form a coalition and political partnership with the opposition (secular) parties, but the disagreement over the approval of the constitution and the activities of the Salafist groups made these two factions refuse to form a coalition, which resulted in the formation of an authoritarian political system in this country. This article is a theoretical research that was written by studying primary sources such as books and articles, and data collection was based on the library method.