The present invention provides a thermoplastic elastomer (TPE), in particular a polyurethane-based thermoplastic elastomer (TPU), that has exceptional elongation, strength, and wear resistance, and in particular has exceptional wear resistance. The present invention provides: a thermoplastic elastomer composition containing A) a thermoplastic urethane elastomer composition having A1) at least one polyol selected from the group consisting of polyether polyols, polyesterpolyols, and polycarbonate polyols, A2) a diisocyanate, and A3) a chain extender, and B) polyrotaxane formed by arranging blocking groups, at both ends of pseudo-polyrotaxane formed by inclusion of the openings of cyclic molecules in a shape skewered by linear molecules, so that the cyclic molecules are not eliminated; and a thermoplastic elastomer derived from this composition.