Literature and art is a theoretical discipline with literary criticism as its basic connotation and theoretical practice as its research object, so it is also called literary theory or literary theory. Guided by Marxist theory, it summarizes and explains the essence of literature and art and the basic laws of creation, appreciation and development in a multi-disciplinary and multi-method way. It is the abstract form and theoretical form of the whole literary research, which provides a theoretical basis for the study of literary criticism and literary history, as well as the whole literary art and human aesthetic culture. It is generally believed that literary theory consists of three parts: literary theory, literary history and literary criticism. Literary theory often studies the basic laws of internal composition and external relations of literature from aesthetics, epistemology, sociology and psychology. The history of literature studies the historical process of the occurrence and development of literature in the past and the internal relationship between its own inheritance and innovation; Literary criticism makes historical and aesthetic judgments on literary works, literary creation and acceptance, and various problems in the literary movement, which is more closely related to the current situation of literature.