The main idea of this thesis is to suggest a new type of reading on Aristotle&#039 / s Poetics. Commentators of Poetics tried to relate it to Aristotle&#039 / s ethical treatises. However, in this research, it will be argued that Poetics should be read under the light of Metaphysics. The interpretation proposed here is based on Aristotle&#039 / s understanding of ousia (substance). The ontological status of artifacts in Aristotle&#039 / s philosophy will be examined while inquiring the relationships between Poetics and Metaphysics. Consequently, I will argue that tragedy is an ousia and attemted to show that Aristotle&#039 / s ontological philosophy is applicable to Poetics. Becouse of the fact that Aristotle treats a tragedy as a partial independent being, I will argue in Aristotelian terms that a tragedy should be judged by its intrinsic values, rather than ethical or rhetorical merits.