A flexible laminated sheet manufacturing method includes thermocompression-bonding an insulation film formed of a liquid crystal polymer onto a metal foil between endless belts to form a flexible laminated sheet. The thermocompression bonding includes heating the flexible laminated sheet so that the maximum temperature of the sheet is in the range from a temperature that is 45° C. lower than the melting point of the liquid crystal polymer to a temperature that is 5° C. lower than the melting point. The thermocompression bonding also includes slowly cooling the flexible laminated sheet so that an exit temperature, which is a temperature of the sheet when transferred out of the endless belts, is in the range from a temperature that is 235° C. lower than the melting point of the liquid crystal polymer to a temperature that is 100° C. lower than the melting point.