Why are the concepts of Modernism, Modernness or Modernity different from each other and what is the place and definition of Modern Art in the face of all these different appearances? In the face of such a structure, Postmodernism shows itself in the field of art by making use of which intellectual foundations, and as a result of all this, how is the definition of Postmodern Art? For this purpose, we will try to comprehend the nature of Modern Art in the first part of our seminar, which is divided into two parts, and the nature of Postmodern Art in the second part and we will try to show the roots of Modern Western Thought and Postmodern Western Thought in order to fully master these two structures. Mehmet Mengü Bachelor of Archeology and Art History at Istanbul University; Non-Thesis Master's Degree-Pedagogical Formation at Balıkesir University Necatibey Faculty of Education; He completed his master's degree with thesis at Ege University, Department of Philosophy. Currently, as a lecturer at Balıkesir University, Faculty of Fine Arts, he gives theory courses in which the History of Western Art, History of Turkish Art, Cultural History and Philosophy of Art are at the center.