PURPOSE: A thermoplastic rubber composition having improved high-temperature creep characteristics and weather resistance, requiring no vulcanization, compris ing a chlorodulfonated polyolefin containing a gelations component, a carboxyl group-containing vinyl chloride resin, a metallic compound and a plasticizer.

CONSTITUTION: (A) A chlorosulfonated polyolefin having preferably 20W50wt% chlorine content (especially polyethylele), having ≥10wt%, preferably 30W98wt% toluene-insoluble gelationous content obtained by subjecting chlorosulfonated polyetylene to intermolecular crosslinking by after-treatment reaction with peroxide is blended with (B) a vinyl chloride resin having 0.05W20wt%, preferably 0.2W10wt% carboxyl group content in a ratio of the component A:B of 0.5:9.5W9:1, (C) preferably 0.1W3mol equivalents based on the carboxyl equivalent of the component B of a monovalent or vibalent metallic compound and (D) preferably 20W100pts.wt. based on 100pts.wt. component B of a plasticizer.