A thermoplastic elastomer composition having: at least one elastomer component selected from the group made of elastomeric polymers (A) each of which has a side chain containing a hydrogen-bond cross-linkable moiety having a carbonyl-containing group and/or a nitrogen-containing heterocycle and has a glass-transition point of 25° C. or below, and elastomeric polymers (B) each of which contains a hydrogen-bond cross-linkable moiety and a covalent-bond cross-linking moiety in a side chain and has a glass-transition point of 25° C. or below; an organically modified clay, a content ratio of which is 20 parts by mass or less relative to 100 parts by mass of the elastomer component; and a polymer (Z) which is a polymer other than the elastomeric polymers (A) and (B), and an SP value of which is 9.0 or more and is greater by 0.5 or more than an SP value of the elastomer component.