To simplify an operation of putting an elastic member through guide passages.

An elastic member attaching device comprises a feeding line for continuously feeding sheets-to-be-attached 20A and 20B, a supplying instrument for continuously supplying elastic members 26 and 28, and a guide 32 for guiding the elastic members 26 and 28 supplied by the supplying instrument to attachment positions on the materials-to-be attached 20A and 20B on the feeding line. In the elastic member attaching device, the guide 32 is made to have an upper section 32A and a bottom section 32B attachably and detachably attached to the upper section 32A, to create guide passages 32X with their circumference closed between the upper section 32A and the bottom section 32B, and to guide the elastic members 26 and 28 to the attachment positions through the guide passages 32X.