To prevent the severing of elastic stretchable members by welding. [Solution] When forming sheet bonding sections (70) which result from welding a first sheet layer (21) to a second sheet layer (22) so that the sheet bonding sections are orthogonal to elastic stretchable members (19) and at intervals in the MD direction by passing through pressurizing and heating the first sheet layer (21) the second sheet layer (22) and long thin elastic stretchable members (19) which are disposed therebetween so as to be continuous in the MD direction between a first roll (90) on the outer circumferential surface of which bonding ridges (91) are provided at intervals in the circumferential direction and a second roll (92) facing said first roll (90) the stated problem is solved by: forming grooves (92d) that are continuous in the circumferential direction on the pressurizing surface of the second roll (92) pressurizing and heating the regions where the elastic stretchable members (19) pass at positions that include the grooves (92d) of the second roll (92) and pressurizing and heating the regions where the elastic stretchable members (19) do not pass at positions other than the grooves (92d) of the second roll (92).
