Thermoplastic olefin elastomer composition

This application is the national phase under 35 U.S.C. § 371 of PCT International Application No. PCT/JP02/02357 which has an International filing date of Mar. 13, 2002, which designated the United States of America. The present invention relates to an olefinic thermoplastic elastomer composition obtainable by dynamically heat treating 5 to 50 parts by weight of a polypropylene resin (A) and 50 to 95 parts by weight of an -olefinic copolymer (B) having a Mooney viscosity ML(100° C.) of 60 to 250 in the absence of a crosslinking agent. The olefinic thermoplastic elastomer composition is characterized in that the glass transition temperature (Tg) in dynamic visco-elasticity measurement derived from the polypropylene resin (A) is lower than that of the polypropylene resin (A) itself and that the -olefinic copolymer (B) is at least one selected from the following (b-1) and (b-2):(b-1) ethylene- -olefinic copolymers which have an ethylene content of 51 to 60 mol % to the total amount of the ethylene- -olefinic copolymer-constituting ethylene and -olefin other than ethylene,(b-2) propylene- -olefinic copolymers which have a propylene content of 60 to 90 mol % to the total amount of the ethylene- -olefinic copolymer-constituting propylene and -olefin other than propylene.