To obtain the subject new composition excellent in economy, permanent antistaticity, flexibility and appearance after molded even in an extremely small amount of a cation-modified copolymer as an antistiatic component to be used, by using a thermoplastic elastomer having specific physical properties.

This composition comprises (A) 100 pts.wt. of a thermoplastic elastomer ≥50 in Shore A hardness (pref. styrene-based or olefin-based thermoplastic elastomer) and (B) 2-15 pts.wt. of a cation-modified copolymer pref. 3,000-30,000 in weight - average molecular weight composed of 70-99mol% of ethylene structural unit of the formula (CH2-CH1), 0-15mol% of acrylate structural unit of formula I (R1 is a 1-4C alkyl) and 1-15mol% of acrylamide structural unit of formula II (R2 is a 2-8C alkylene; R3 to R5 are each a 1-12C alkyl or 7-12C arylalkyl; X is a halogen, CH3OSO3, etc.).