PURPOSE: To obtain the subject composition, containing a polyamide-imide resin prepared by blocking COOH groups with vinyl ethers, etc., a compound having plural functional groups reactive with the COOH groups and a heat latent catalyst and excellent in low-temperature curability and preservation stability.

CONSTITUTION: This heat-resistant resin composition is obtained by blending (A) a polyamide-imide resin, prepared by thermally reacting 4,4'-diphenylmethane diisocyanate with trimellitic anhydride, etc., adding n-butyl vinyl ether, etc., to the resultant polyamide-imide resin and blocking the carboxyl groups in the polyamide-imide resin with vinyl ethers or vinyl thioethers and having ≥10000 number-average molecular weight with (B) a compound having ≥2 reactive functional groups chemically bindable to the carboxyl groups in the component (A) such as epoxy, amino, hydroxy or isocyanate group and (C) a heat latent catalyst such as a protonic acid salt, a phosphoric or a sulfonic ester.