A elastically deformable string includes an outer layer and a core material placed inside the outer layer, wherein the outer layer has knob parts that are constituted by loosely woven outer layer yarns and elastically deformable, and link parts that are constituted by densely woven outer layer yarns and have a smaller diameter than the knob parts, wherein the loosely woven outer layer yarns are woven more loosely than are the densely woven outer layer using same yarns, and the core material is constituted by a stretchable string and placed inside the knob parts in a slackened and/or meandering state. The elastically deformable string is suitable for shoes, for example, as a shoelace which does not require knots.