To provide a method for thermally treating a web, by which the web is treated without producing thermal treatment temperature irregularity, and to provide a thermal treatment apparatus using for the method.

This method for thermally treating the web is characterized by imparting a solvent, preferably water, to the conveyed web and then thermally treating the web. The method for thermally treating the web, wherein the solvent is imparted by spraying or with a touch roll. The method for thermally treating the web, wherein the solvent is water. The method for thermally treating the web, wherein the thermal treatment is carried out by circulating nitrogen gas.