A metal composite film having an excellent heat resistance and adhesion, suited for flexible printed circuit boards capable of forming fine wirings, as well as a production process thereof, is disclosed. The metal composite film comprises an insulating film; a thermoplastic polyimide layer(s) formed on at least one surface of the insulating film; and metal layers formed on the surface of each of the thermoplastic polyimide layer(s), which metal layers are formed by electroless plating and then by electrolytic plating, respectively. Since this metal composite film has an excellent heat resistance and adhesion, and maintains the excellent adhesion after forming fine wirings, it is suitably used as a high density flexible printed circuit board having fine circuits.