PURPOSE: To obtain the titled tough composition useful as a low-cost thermoplastic elastomer or a solubilizing agent for polyamide and polyolefin, by mixing a specific polyamide elastomer with a polyolefin resin in the presence of a peroxide.

CONSTITUTION: An elastic composition (A) is prepared by kneading and reacting (I) 10W90% polyamide elastomer having a polyamide hard segment containing nylon m component (m≥10) and/or nylon mn component (m and/or n are≥10) as a component and a soft segment of polyether and/or polyester (e.g. polytetramethylene ether) with (II) 90W10% polyolefin resin in the presence of (III) a peroxide (e.g. dicumyl peroxide). The composition (A) is mixed under melting with (B) nylon m (m≥10) or nylon mn and (C) a polyolefin compolymer resin. The contents of the component (A) and the polyamide component in the whole composition are 5W50% and 40W95%, respectively.