Abstract: In a modern world of eco-crisis, eco-criticism thus comes into vision. It devotes to de-root the sources of thoughts and culture which cause eco-crisis nowadays and, therefore, make it possible to revolutionize human thoughts and culture and contribute to the future and favor of ecology. With their great influence, classic literatures become an important part in eco-criticism. As a significant poet in Irish literature, Yeats has gone through the changes from Romanticism to Modernism. Also, it was a time agricultural Ireland transformed into an industrial one. Irish ecology was faced with a disaster. This paper is to decode the ecological description in Yeats poems through analysis of some his poetry works.