PURPOSE: To prepare a laminated sheet different in the thickness of the metal plate thereof and to individually replace rolls by providing a mechanism capable of bringing a heating roll to a driving state and a non-driving state.

CONSTITUTION: The shaft of a main adhesive roll (heating roll) 9 is connected to the shaft of a speed reducer 7 by a clutch 8 and heated to manufacturing temp. in a driving state. After the main adhesive roll 9 is uniformly heated, the shaft of the roll 9 and the shaft of the speed reducer 7 are out off by the clutch to set the roll 9 to a non-driving state. Next, an upper metal plate 1 and a lower metal plate 1' are heated to temp. directly above the softening point of a resin by means of heated temporary bonding rolls 2, 2' to temporarily bond resin films 4, 4' to the metal plates. The temporarily bonded metal plates are further heated to the m.p. of the resin or higher by main bonding rolls 3, 3' (each same to the roll 9) heated to manufacturing temp. to press and fuse three members of metal plate-resin film-metal plate to finish a laminated sheet.