The present invention provides a non-flammable heat-resistant resin composition that is provided with (A) modified polyamideimide resin, (B) thermosetting resin and (C) organic phosphor-based compound, and a cured film, obtained from the non-flammable heat-resistant resin composition, exerts a storage elastic modulus of 700 MPa or less, a coefficient of thermal expansion of 5.times.10.sup.-3/K or less and an internal stress of 20 MPa or less, in a temperature range of 25 to 250.degree. C., and the present invention also relates to an adhesive film using the resin composition.