PURPOSE: To produce a laminated sheet of stable quality without differentiating a heating condition even when the thickness of the laminated sheet is different.

CONSTITUTION: A multi-stage press for molding a laminated sheet is used and the temp. of the press is controlled in such a state that the average value of the temp. of hot plates measured at any time by the temp. sensor incorporated in the hot plate and the temp. of the hot plates measured by placing the temp. sensor at the area most separated from the hot plates of the laminating material held between the hot plates is set as an upper limit value. In the apparatus used in this method, the temp. converter 2 connected to the temp. sensor 7 incorporated in the hot plates 1 and the separate temp. converter 3 connected to the temp. sensor 8 inserted in the center layer of the laminating material held between the hot plates are arranged in parallel to be connected to one temp. setting device 3 and further successively connected to a control part 4 and a heating medium flow rate control valve 5 and the other terminal of the flow control valve 5 is divided and one of the divided terminals is connected to a heating medium source and the other one of them is connected to the respective hot plates.