To provide a composite film for a bottom material having high impact strength, good in moldability, transparency and rigidity and excellent in the easy peelability with a lid material film.

An easy peel co-extrusion composite film is constituted so that a heat-sealble resin layer 1 is arranged to one outermost layer and an amorphous polyester resin layer 5 with a thickness of 200-500μm is arranged to other outermost layer and a barrier resin layer 3 composed of an ethylene/vinyl acetate copolymer saponified matter layer or consisting of a polyamide resin layer and an ethylene/vinyl acetate copolymer saponified matter layer is arranged as an intermediate layer and an oxidizing layer 11 is formed on the surface of the heat-sealable resin layer 1.