Thermoplastic elastomer composition and molded article

Provided are: a thermoplastic elastomer composition which is capable of further increasing tan [delta] at 23 DEG C and a molded article which is produced using the thermoplastic elastomer composition and which has excellent vibration damping properties. The thermoplastic elastomer composition according to the present invention is obtained by dynamically crosslinking a mixture in the presence of (D) a crosslinking agent, the mixture includeing: (A) an elastomer having a glass transition temperature of 0 DEG C or less, having at least one of a structural unit obtained by hydrogenating a structure derived from isoprene and a structural unit derived from isobutylene, and having an unsaturated bond; (B) an alpha-olefin-based thermoplastic resin (excluding a 4-methyl-1-pentene-alpha-olefin copolymer and a case corresponding to the following (E)); and (C) an aromatic petroleum resin, an aliphatic petroleum resin, an aliphatic/aromatic petroleum resin, a dicyclopentadiene petroleum resin, a terpene resin, a rosin der