The production of religious knowledge takes place in a systematic and methodical structure with tools and resources. The role of each of the tools in a detailed exploration is very important to reach religious understanding. This is not only in jurisprudential studies, but in all religious studies based on inferential and ijtihad approach. Without paying attention and using the necessary tools and resources, an achievement called religious knowledge will not be available to the scholar and researcher of religion. Intellect has a special place among knowledge-building tools. In this research, we will answer this question, what role does reason play in the production of religious knowledge and its evaluation in Imam Khomeini's thought system? Is reason the only tool for evaluating knowledge? Is intellect not a criterion for accepting knowledge? What is the importance of reason in Imam's religious epistemology system? According to the findings of this article, among human knowledge, intellectual knowledge is the best tool even for understanding intuitive and mystical knowledge, and it has significant efficiency in explaining revealed knowledge. We will follow these issues in the works of Hazrat Imam with a descriptive and analytical method.