Disclosed are novel polyamideimide elastomers obtained by reaction of carboxyl-telechelic polymer(s) having a molecular weight of 500 to 10,000 aromatic diisocyanate(s), trimellitic acid anhydride and a dicarboxylic acid having 4 to 18 carbon atoms in a particular proportion. The polyamideimide elastomers have excellent heat resistance, oil resistance and low temperature characteristics and have mechanical properties which are comparable to those of polyurethane elastomers. Further, the said elastomers have a particular characteristic that they may retain a rubber-like property even at a high temperature.