Abstract: Ontology is a chief field of western philosophy.Using the relation of ontology and cosmology ,science and philosophy as the standard of dividing the state of philosophy,we can devide the western philosophy into epistemology ontology and meaning ontology.The ancient and modern philosophy is epistemology ontology,the philosophy of post-Hegel is meaning ontology.From the view of the philosophy style,the transformation of Western Philosophy Ontology is that from epistemology ontology to meaning ontology.

Key words: western philosophy, epistemology ontology, meaning ontology