A composite stretchable member production apparatus for producing a composite stretchable member comprising two sheets (2a, 2b) and a plurality of elastic elements sandwiched between the two sheets (2a, 2b), by bonding the two sheets (2a, 2b) together and further bonding each of the elastic elements to the sheets (2a, 2b), while conveying the two sheets (2a, 2b) along a longitudinal direction thereof, the composite stretchable member production apparatus comprising: a bonding device which bonds each of the elastic elements to the sheets (2a, 2b) and further bonds the sheets (2a, 2b) together, by means of welding, in a state in which the elastic elements are sandwiched between the two sheets (2a, 2b) being conveyed; and a guide device which guides, to the bonding device, the two sheets (2a, 2b) and the elastic elements in such a manner as to enable each of the elastic elements to be sandwiched between the two sheets (2a, 2b) while extending in the longitudinal direction of the sheets (2a, 2b), wherein the bonding device comprises: a conveyance roller having an outer peripheral surface rotatable about a given axis to convey the two sheets (2a, 2b) with the elastic elements sandwiched therebetween, in the longitudinal direction of the sheets (2a, 2b); and a clamping and pressing device which is opposed to the outer peripheral surface of the conveyance roller, and clamps and presses the two sheets (2a, 2b) with the elastic elements sandwiched therebetween, in cooperation with the outer peripheral surface, the bonding device being configured to apply heat to the sheets (2a, 2b) between the conveyance roller and the clamping and pressing device, and wherein the outer peripheral surface of the conveyance roller is formed with at least one convex section protruding toward the clamping and pressing device, the convex section extending along a line intersecting a conveyance direction of the conveyance roller, and having a plurality of grooves lying in spaced-apart relation to each other on the line intersecting the conveyance direction of the conveyance roller and each extending in the conveyance direction of the conveyance roller, characterized in that the guide device comprises a guide member having a distal edge opposed to the outer peripheral surface of the conveyance roller, and a base edge disposed farther away from the conveyance roller than the distal edge, the guide member being configured to guide the plurality of elastic elements to the outer peripheral surface of the conveyance roller, in a state where the plurality of elastic elements are spaced apart from each other in a direction parallel to the axis of the conveyance roller, the distal edge of the guide member is formed with a plurality of notches each for holding a respective one of the elastic elements, at positions spaced apart from each other in a direction parallel to the axis of the conveyance roller, and the notches are arranged at positions corresponding to the grooves. a bonding device which bonds each of the elastic elements to the sheets (2a, 2b) and further bonds the sheets (2a, 2b) together, by means of welding, in a state in which the elastic elements are sandwiched between the two sheets (2a, 2b) being conveyed; and a guide device which guides, to the bonding device, the two sheets (2a, 2b) and the elastic elements in such a manner as to enable each of the elastic elements to be sandwiched between the two sheets (2a, 2b) while extending in the longitudinal direction of the sheets (2a, 2b), wherein the bonding device comprises: a conveyance roller having an outer peripheral surface rotatable about a given axis to convey the two sheets (2a, 2b) with the elastic elements sandwiched therebetween, in the longitudinal direction of the sheets (2a, 2b); and a clamping and pressing device which is opposed to the outer peripheral surface of the conveyance roller, and clamps and presses the two sheets (2a, 2b) with the elastic elements sandwiched therebetween, in cooperation with the outer peripheral surface, the bonding device being configured to apply heat to the sheets (2a, 2b) between the conveyance roller and the clamping and pressing device, and wherein the outer peripheral surface of the conveyance roller is formed with at least one convex section protruding toward the clamping and pressing device, the convex section extending along a line intersecting a conveyance direction of the conveyance roller, and having a plurality of grooves lying in spaced-apart relation to each other on the line intersecting the conveyance direction of the conveyance roller and each extending in the conveyance direction of the conveyance roller, characterized in that the guide device comprises a guide member having a distal edge opposed to the outer peripheral surface of the conveyance roller, and a base edge disposed farther away from the conveyance roller than the distal edge, the guide member being configured to guide the plurality of elastic elements to the outer peripheral surface of the conveyance roller, in a state where the plurality of elastic elements are spaced apart from each other in a direction parallel to the axis of the conveyance roller, the distal edge of the guide member is formed with a plurality of notches each for holding a respective one of the elastic elements, at positions spaced apart from each other in a direction parallel to the axis of the conveyance roller, and the notches are arranged at positions corresponding to the grooves.