Epistemological truth and religious truth is a two different thing; as fundamental issues in epistemology, epistemological truth to be sure is result of human achievement built in a form of theory, while religious truth is gift from God, moreover, it has been His attribute that must to be penetrated and believed in. Truth in epistemology may be different with truth in religion, although is not certainly be in contradiction. In such this framework of thought, this thesis intended to explore theory of truth in epistemology of Kant and Suhrawardi. Immanuel Kant is Philosopher in a German Idealism age, meanwhile Suhrawardi is a Theosophist-Philosopher who very intelligently arise Islamic Philosophy in age of Caliph of Şalah al-Din al-Ayyübi. It will be two purpose of this thesis at least, understanding distinctive feature of Suhrawardi and Kant's theory of truth and contribution springs from this theory.