PURPOSE: To manufacture a product roll having high quality without using an expensive shaft body at the time of manufacturing a core-less roll paper.

CONSTITUTION: In a web winding process, plural cores 20, 20... made of inexpensive material such as tubular material or cylindrical material are used, and these cores are supplied to a web winding part 12 with a space A between each core 20, 20, and the liquid for adhering web is sprayed to the wind-up starting end of the web in a range of a predetermined small length, and the web is wound, and thereafter, a web at a product length is wound to form a long size web wound material T1 with core. Continuously, a drying process for drying the long size web wound material T1 with core, a cutting process for cutting the dried long size web wound material T1 with core at a product length, and a core drawing process for drawing the core 20 from a short size web wound material T2 with core are performed.