The invention discloses an elastic-tooth returning-straw burying operation assembly, and belongs to agricultural machines. N elastic teeth arranged in double-end helical line shapes are evenly installed on an assembly shaft in the axial direction, the elastic teeth are formed by connecting fixing installing sections and burying operation sections, the fixing installing sections are in arc-surfaceshapes as a whole, radiuses of the inner surfaces of the arc surfaces of the fixing installing sections are matched with the radius of the outer surface of the assembly shaft, the burying operation sections are in involute surface shapes as a whole, and the cross sections of the burying operation sections are rectangular. The elastic-tooth returning-straw burying operation assembly is novel in structure, reasonable and simple; the burying rate of returning straw is high, the burying depth is large, stress of the assembly is balanced during operation, running is stable, and the land surface issmooth and clean after operation.