This applied research aimed at finding out the principles of rational training based on the sayings of Imam Reza (Pbuh). It was intended to answer this question: "what are the principles of rational training based on Imam Reza's sayings?" Having gathered the data through library method, and having analyzed the data by content analysis, the researchers found out that these principles can be divided into two categories. The first refers to general principles including both theoretical and practical rationalities. They include the principles of moderation, harmony between knowledge and practice, coordination with innateness, rational freedom. Specific principles were divided into -two categories: 1. principles based on theoretical rationality, including cohesion between acquiring experience and knowledge, thoughtfulness, distinction between useful knowledge and experience from useless ones, the necessity of having scientific morality, knowledge seeking, coordination between rationality and science, the necessity of prevention of giving knowledge to evil people. 2. the practical rational specific principles, which included following the phases of purification of soul, capability- based responsibility, and the necessity for rationality to follow the commands of God.