A glass roll manufacturing method comprising: a molding step (S1) in which the downdraw method is used to convey a glass film (G) while continuously molding the glass film (G); a temporary rolling step (S3) in which a base glass roll (14) is manufactured by layering a protective film (F1) onto the glass film (G) and then rolling the same up at the downstream end of the conveyance path used in the molding step (S1); and a main rolling step (S4) in which a glass roll (16) is manufactured by rolling out and transporting glass film (G) from the base glass roll (14) at the downstream end of the transport path, layering a protective film (F2) onto the glass film (G), and re-rolling the glass film (G). In addition, the tension acting on the glass film (G) in the winding direction is increased in the main rolling step (S4) relative to the temporary rolling step (S3).