Abstract：This paper deals with the technical term "motif" indispensable to the study of comparative mythology which has its special objects of study but lacks special theoretical methods and technical terms. Holding that "motif", as a fundamental element of myth, should be the essential concept of comparative mythology and thus should serve as the logical foundation of the building of comparative mythology theory, it studies its origin , meaning in different disciplines, definition in comparative mythology, difference from theme, image and archetype, and special function in mythology study.
