A method of manufacturing a fishing line guide which has a guide ring for guiding a fishing line and is attachable to a tubular rod (1120, 1130, 1140, 1150) of a fishing rod, the method comprising: working a ring support composed of a metallic thin plate, the ring support including: a ring holding portion holding the guide ring; and a ring supporting portion integrally formed with the ring holding portion, wherein a through-hole is formed in the ring holding portion as a ring holding hole such that a reinforcing flange in contact with an outer peripheral surface of the guide ring is formed; and injection molding an attachment portion having an annular shape, which has an inner peripheral surface to be fitted with an outer peripheral surface of the tubular rod (1120, 1130, 1140, 1150), from a resin material by using the ring support as an insert such that a lower portion of the ring supporting portion is embedded in the attachment portion, wherein the working the ring support comprises: forming the through-hole in a metal sheet; after the forming the through-hole, forming the reinforcing flange, with which the guide ring is fitted at an inner peripheral surface of the reinforcing flange, by making an edge portion surrounding the through-hole of the metal sheet protrude from the metal sheet; bending the metal sheet such that at least one bending portion (1331, 1332) is formed in the metal sheet; and blanking the ring support from the metal sheet. working a ring support composed of a metallic thin plate, the ring support including: a ring holding portion holding the guide ring; and a ring supporting portion integrally formed with the ring holding portion, wherein a through-hole is formed in the ring holding portion as a ring holding hole such that a reinforcing flange in contact with an outer peripheral surface of the guide ring is formed; and injection molding an attachment portion having an annular shape, which has an inner peripheral surface to be fitted with an outer peripheral surface of the tubular rod (1120, 1130, 1140, 1150), from a resin material by using the ring support as an insert such that a lower portion of the ring supporting portion is embedded in the attachment portion, wherein the working the ring support comprises: forming the through-hole in a metal sheet; after the forming the through-hole, forming the reinforcing flange, with which the guide ring is fitted at an inner peripheral surface of the reinforcing flange, by making an edge portion surrounding the through-hole of the metal sheet protrude from the metal sheet; bending the metal sheet such that at least one bending portion (1331, 1332) is formed in the metal sheet; and blanking the ring support from the metal sheet. forming the through-hole in a metal sheet; after the forming the through-hole, forming the reinforcing flange, with which the guide ring is fitted at an inner peripheral surface of the reinforcing flange, by making an edge portion surrounding the through-hole of the metal sheet protrude from the metal sheet; bending the metal sheet such that at least one bending portion (1331, 1332) is formed in the metal sheet; and blanking the ring support from the metal sheet.