The Holy Quran, which is a comprehensive source of religious knowledge, regards "freedom of expression" as one of the basic human rights and has given it a high position . This is considered one of the fundamental strategies in the Islamic government. "Freedom of expression", like other phenomena, has limits and frameworks, which are necessary to be defined in the literature of the Holy Qur'an and the thought of Shia and Sunni commentators, considering the destructive and insulting productivity of those who are ignorant of it. The purpose of this article is to answer the question, what are the criteria of "freedom of speech" in the Holy Quran based on the viewpoint of the commentators of the two school of thoughts (Shai and Sunni)? In order to achieve its goal, the article is written in a qualitative manner and by using the descriptive-analytical method and inferential thematic interpretation and library and software tools, referring to the Holy Quran and exegesis sources, collecting and analyzing the verses regarding the limits of freedom of expression. Searching in the verses and interpretations shows that; The freedom to express beliefs can be proved as a principle of the Qur'an; But not absolutely and unconditionally; Rather, it is based on rulings such as observing divine limits, observing rational and logical quorums, observing the interests of Islamic society, prohibiting creating tension, breaking unity, rumor-mongering, insulting, mocking expressions and things that cause corruption. And it becomes personal or social ruin. Regulating "freedom of speech" while protecting the principle of freedom of expression, closes the path of destructive expressions and prevents destructive statements that are against personal and social interests.