To solve problems such that an adhesive layer having a fairly lower glass transition temperature than that of a substrate film, is melted and attaches to a punching machine by a high frictional heat on punching, for inducing frequent exchanges of the punching machine and the increase of washing costs, and decreasing the productivity of a leading frame attached with the composite film.

This composite film having a structure of laminating the adhesive on both surfaces of the substrate film is provided by having a relationship of the glass transition temperature of the adhesive, Tg satisfying the formula and formula 6: 135°C≤Tg≤185°C, by taking the thickness of the composite film as T and the total thickness of adhesive layer of both sides as TA, and the lead frame attached with the composite film is also provided.