A composite stretchable sheet (10) having, alternatingly in the direction in which elastic members (13) are extended, convex parts (14) and concave parts (15) extending in a direction orthogonal to the direction in which the elastic members (13) are extended. The three-dimensional shape of the convex parts (14) and the concave parts (15) is maintained in a state in which the composite elastic sheet (10) is in a maximally stretched state. Sheet base materials (11, 12) of the composite stretchable sheet (10) have high stretch-processed regions (16) and low stretch-processed regions (17). The high stretch-processed regions (16) and the low stretch-processed regions (17) extend along the direction in which the elastic member (13) is extended, the regions (16, 17) being alternatingly positioned in the direction orthogonal to the direction in which the elastic members (13) are extended. The elastic members (13) are disposed in the low stretch-processed regions (17).
