A method of manufacturing a glass roll, includes: a forming step (S1) of forming, while conveying a glass film, the glass film by a downdraw method; a temporary rolling step (S3) of rolling the glass film while superposing a protective film on the glass film at a downstream end of a path of the conveying in the forming step (S1), to thereby manufacture a source glass roll; and a main rolling step (S4) of unrolling, while conveying the glass film to a downstream side, the glass film from the source glass roll, and then rerolling the glass film while superposing a protective film on the glass film at a downstream end of a path of the conveying, to thereby manufacture a glass roll. Higher tension in a rolling direction is applied to the glass film in the main rolling step (S4) than in the temporary rolling step (S3).