PURPOSE: To eliminate deformation during load of tension and to improve productivity of winding, coating, etc., by forming nonelastic belt parts along the longer direction on both selvadge parts of an elastic base material.

CONSTITUTION: A web of conjugate polyester yarn or conjugate polypropylene yarn having crimping potential is needled and crimped by heat treatment in a tension-free state to give elastic nonwoven fabric 3 in continuous lengths. Then, a molten polyethylene resin is applied to both selvadge parts of the elastic nonwoven fabric 3 in continuous lengths in parallel with the longer direction by given width and solidified to form nonelastic belt parts 2. Or, both the selvadge parts are cut by a heat cutter by given width, the cut edge parts are sealed to form the nonelastic belt part 2. Consequently, variability in length and width directions caused by tensile strength during winding and coating with a skin patch is eliminated and production rate of base material is increased to improve productivity.