A method of producing a clothing article including the steps of (a) joining first continuous webs 120a and 120b having stretchability in the longitudinal direction thereof both in a longitudinally stretched state along an edge portion thereof to a longitudinally substantially inextensible second continuous web 120c to make a continuous composite sheet 120, (b) joining the composite sheet 120 obtained in step (a) on its side to a member 130 of the clothing article to make a web assembly 110, and (c) cutting the web assembly 110 obtained in step (b) to length.