The production method of the present invention is characterized by comprising a temporary bonding step of temporarily bonding a first sheet comprising a thermoplastic resin non-oriented film layer and a thermoplastic adhesive resin layer laminated on one surface of the thermoplastic resin non-oriented film layer and a second sheet comprising a heat resistant resin oriented film layer and an aluminum foil layer laminated on one surface of the heat resistant resin oriented film layer by passing the first sheet and the second sheet between a pair of rolls in a state in which the thermoplastic adhesive resin layer and the aluminum foil layer are brought into contact with each other to press them while heating in a state in which the thermoplastic adhesive resin does not melt to thereby obtain a pre-laminated sheet, and a complete bonding step of integrally bonding the first sheet and the second sheet by heating the pre-laminated sheet to melt the thermoplastic adhesive resin. This production method can attain a reduced plant cost and high speed production.