A resin composition resulting in a cured article which is excellent in balance among mechanical strength, surface smoothness, and light transmittance, a method for producing a cured article, a cured article, and a flexible substrate or flexible display including the cured article. The resin composition includes a polyamic acid having a structural unit represented by the following formula (1), a cellulose compound having a weight average molecular weight of 60,000 or less, and an organic solvent. In the formula (1), A is a tetravalent organic group and B is a divalent organic group.