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 Şalāh al-Dîn 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. To reveal these problems, Researcher resort to epistemological approach; philosophical perspective about knowledge and its way of achievement. Source, methodology, and validity of knowledge then, as principal problem in epistemology will be the main study in this thesis. More than just comparing thought of two philosophers, this thesis involved actively to reconcile two great ideas are born of different traditions. For this, literature collected will be analyzed in compare and contrast, before combined with heuristic analysis to get a new case from two meetings. This study obtain the result, either Kant or Suhrawardi emphasize the importance of self-consciousness as fundamental principle to achieve truth. This is due to the "selfconsciousness" human is not only reach, appearance of object but also go into reality of object in themselves/Kamā huwa. Methodically, understanding the reality of the object can be done with the "Categories" of Kantian or Suhrawardi's accumulation all of its essence (yajma' jamî'u dhätiyyātihā). However, these equipment of intelligence must be exceeded to reach reality of metaphysic. Either Suhrawardi or Kant affirmed that two levels of knowledge is only the first two steps to reach the metaphysical knowledge as highest hierarchy. Kant's concept of "Transcendental Idea" and Suhrawardi's Mushähadah and Nür al-Anwar can meet and clarify this metaphysical knowledge one another. Therefore, epistemological truth is hierarchy of truth as hierarchy of knowledge as well; knowledge on sensibility is basic knowledge owned by majority of human. Meanwhile reason is a scientific knowledge possessed by Scientists. Highest knowledge is knowledge on intellect, as metaphysical knowledge inherited by Metaphysicians, Theologians, Ulamā, and Hukama. If the process is valid, the epistemological truth absolutely will deliver us to religious truth, even the truth of God as The Truth in fact. This study shows us that His Truth is truly a room for other truths in particular. Therefore, it is not true to put the epistemological truth with religious truth vis a vis. As is not true to confronting knowledge and religion vis a vis. Finally, this study is focused on the theory of truth in epistemology. It is to be sure, there are another side of attractive idea from these philosophers, then the further study is quite interesting to do. For example of how to regard the theory oftruth as part of epistemological realm with the truth behaviors included in area of ethical studies.