A method of manufacturing a paper bag

Problem to be solved: To provide a technique for easily manufacturing a paper bag having a complicated configuration having a resealing function and an easy opening function. [Solution] the method for manufacturing a paper bag includes: Performing an unnecessary portion cutting step, a cylindrical portion forming step, a bottom forming step, and a sealing seal sticking step on a single first line; A cutting step of cutting the release paper coated with the sealing adhesive for each paper piece unit including two coated portions in a second line different from the first line and a separation step of separating the paper piece into a sealing seal including one coated portion are performed, the sealing seal is stuck to the sealing flap of the cylindrical part separated in the cylindrical part step, One of the sealing seals is stuck to one side of the perforation or to the outer surface of...