A manufacturing method of a composite sheet of an absorbent article, the method includes joining a continuous body of an elastic member in a predetermined meander pattern in respect to a continuous body of a sheet transported continuously in a transporting direction, the method includes: transporting the continuous body of the sheet by wrapping the continuous body of the sheet around an outer circumferential face of a transporting roll that rotates in a direction along the transporting direction； and joining the continuous body of the elastic member to a portion of the continuous body of the sheet wrapped around the transporting roll by feeding the continuous body of the elastic member to the continuous body of the sheet via an oscillating arm that oscillates in an intersecting direction intersecting the transporting direction with a spindle portion as a swivel fulcrum, wherein the oscillating arm includes an oscillating end side roller arranged at an oscillating end side of the oscillating arm and a spindle portion side roller arranged at a spindle portion side, wherein in the joining, the continuous body of the elastic member supplied toward the spindle portion side roller through a supply route along a rotational central axis direction of the spindle portion is put around an outer circumferential face of the spindle portion side roller and an outer circumferential face of the oscillating end side roller successively and guided to the continuous body of the sheet, and a driving force to make the oscillating arm oscillate is input at a position on the oscillating arm different from the spindle portion.
