The method of manufacturing the secondary paper roll for the tissue paper products including: a multi-ply forming step (51) of multi-ply forming single-sheets S11 and S12 from primary paper rolls, reeled out from the plural primary paper rolls JR in the continuous direction so as to form a multi-ply continuous sheet S2, a chemicals applying step (53) of applying chemicals to the multi-ply continuous sheet S2, a slitting step (55) of slitting the multi-ply continuous sheet S2 into each product width of the tissue paper products or several fold widths thereof, and a winding step (56) of coaxially winding the respective slit multi-ply continuous sheets S2 so as to form plural secondary paper rolls R of each product width of the tissue paper products or several fold widths thereof.