PURPOSE: To manufacture a forming tube with a release agent layer efficiently by spirally winding liner paper, to which the release agent layer is formed, on a mandrel, forming a cylindrical body, heating the cylindrical body and curing the release agent layer.

CONSTITUTION: Ribbon-shaped first liner paper 2 is wound spirally on a columnar mandrel 1, and second liner paper 3 is wound helically on the first liner paper 2. A release-agent applicator 10 is installed to a transfer path reaching the mandrel 1 of first liner paper 2, and a surface brought into contact with the mandrel 1 of first liner paper 2 is coated with a release agent such as silicone, paraffin, etc. by the applicator 10. Since a cylindrical body A is moved in a heating furnace 40, a release agent layer and an adhesive layer are cured, and the overlapping sections of second liner paper 3 are joined mutually, thus forming a forming tube having the release agent layer on a surface.