To reduce operation time and ensure strength of a covering member.The method includes; causing the first sheet to memorize a shape of curvature having a predetermined radius of curvature by curing a first resin while holding the first sheet with the predetermined radius of curvature, the first sheet being impregnated with the first resin (S1); wrapping the first sheet around a radially expandable cylindrical packer and tentatively fastening the first sheet to the packer, wherein the packer has a radius that is smaller than the predetermined radius of curvature (S3); forming a laminated sheet assembly by attaching a plurality of sheets to each other with a second resin (S2); forming the covering member by wrapping the laminated sheet assembly around an outer surface of the first sheet via a third resin and tentatively fastening the laminated sheet assembly, the first sheet being wrapped around the packer (S4); applying a fourth resin to an outer surface of the laminated sheet assembly of the covering member and inserting the packer into a cylindrical tube (S5); radially expanding the packer in the cylindrical tube to release the tentative fastening of the first sheet and the laminated sheet assembly, thereby pressing the covering member against an inner wall of the cylindrical tube via the fourth resin (S6); pulling out the packer from the cylindrical tube (S7); and curing the second (S8).