The present invention provides a flat film carrier tape for mounting electronic devices thereon which tape can enhance reliability of a semiconductor chip mounting line. The film carrier tape includes a continuous insulating layer, a wiring pattern formed of a conductor layer provided on a surface of the insulating layer, a row of sprocket holes provided along respective longitudinal edges of the insulating layer, which said row of sprocket holes are at the outer sides of the wiring pattern, and a metallic layer formed around said row of sprocket holes, wherein the metallic layer is provided in a discontinuous manner in the longitudinal direction of the insulating layer by provision of slits on the insulating layer at intervals of three to eight said sprocket holes. Through employment of the above structure, stress produced between the metallic layer and the insulating layer is appropriately released by the provided slits, thereby preventing wavy deformation along the longitudinal edges of the both sides of the film carrier tape.