Abstract: In his later years，Engels conducted an in-depth study on Marxist legal theory，and made considerable achievements which are still of contemporary value.In his The Origin of the Family，Private Property and the State，he illustrated the difference and connection between folklore and civil law，maintaining that folklore refers to the manners and customs of the people，and civil law is the generic term of legal norms which adjust the property relationship and personal relationship of the equal parties.Folklore is developed through experience after generations，and it is the origin of civil law.Movement of basic contradictions in a given society is the motivation of the replacement of folklore by civil law.Besides，the generation of civil law is also due to national and cultural conflicts，in which folklore fails to control or adjust social conflicts.Today，Engels’s legal thought in his later years is still an important methodology to study civil law，and this unique perspective may reveal the connection and difference between folklore and civil law.

Key words: Engels, legal thought, folklore, civil law