Urethane-modified polyimide resin solution

The present invention addresses the problem of providing a novel urethane-modified polyimide resin solution that uses absolutely no high boiling-point, highly hygroscopic polar solvent. A urethane-modified polyimide resin solution containing: a urethane-modified polyimide resin (A) containing 30-90 mol% of amide-imide units (i) constructed from a trimellitic acid derivative and an aromatic diisocyanate component and 10-70 mol% of urethane units (ii) constructed from a compound of a specific structure and an aromatic diisocyanate component, taking the total structural components of the urethane-modified polyimide resin (A) as 100 mol%; and one or more organic solvents (B) selected from the group consisting of cyclohexanone and cyclopentanone.