PROBLEM TO BE SOLVED: To inhibit necking caused in a first continuous sheet in a manufacturing process in manufacturing a composite of a continuous sheet.SOLUTION: In this method for manufacturing a composite of a continuous sheet, an elastic slip-like sheet is cut from a first continuous sheet which exhibits elasticity in the continuous direction by elongation in the continuous direction to generate a slip-like sheet, and the slip-like sheet is joined in a superposition on a second continuous sheet to manufacture a composite of the continuous sheet. While the first continuous sheet is wrapped in the shape of S round an upstream roll and a downstream roll rotating with the outer peripheral surfaces thereof opposite to each other along the continuous direction of the first continuous sheet, a difference in peripheral velocity value is made between the upstream roll and the downstream roll, whereby the first continuous sheet is elongated in the continuous direction at a predetermined magnification to exhibit elasticity in the first continuous sheet, the first continuous sheet where the elasticity is exhibited is cut in the elongated state to generate an elongated slip-like sheet, and the generated elongated slip-like sheet is jointed to the second continuous sheet.
