Folk song and folk rhyme in the rear area during the anti-Japanese war is an important part of the anti-Japanese literature which has made outstanding contributions to the literary and social influences. Due to the impacts of social historical and political factors, it is not cared for a long time and has become a blank item in the study of the anti-Japanese literature. However, it should be evaluated from the literary reality at that time and from the national stand and literary concept of historicism. Its prosperity is mainly reflected in four aspects: first, the duration is long, the authors are many and the number is large; second, the geographical distribution is wide, and the influence range is wide; third, the material themes are highly social, rich and profound; fourth, the literary forms are flexible, various and brilliant. The reasons for its prosperity are mainly as following: first, it adapts to the needs of the literary characteristics during the anti-Japanese war; second, the vigorous promotion of literary societies and organizations; people from all walks of life actively participate in the creation; fourth, the strong advocacy and support in theory field; fifth, the generous help of the publishing industry.