Disclosed is a thermoplastic elastomer composition which comprises (A) a thermoplastic resin containing a polystyrene resin, (B) a rubber-like polymer obtained by partially or completely crosslinking an ethylene-&agr;-olefin copolymer and (C) a compatibilizing agent, the amount of the component (B) being 40-90 parts by weight and the amount of the component (C) being 0.1-40 parts by weight based on 100 parts by weight of the components (A), (B) and (C) in total. According to the present invention, an elastomer composition excellent in abrasion resistance can be provided.