More particularly, the present invention relates to a method of manufacturing a buoy by wrapping and molding a synthetic resin roughness-type internal reinforcing body, and more particularly, The inner reinforcing body in which the groove portion and the protruding portion are continuously formed in the gap is cut to a predetermined length, the side finishing plate is fixed by welding from both sides, and the inner reinforcing body is wrapped with heat shrinkage on the outer side of the entire surface without water The present invention relates to a buoy manufacturing method for wrapping and molding a synthetic resin roughness-type internal reinforcing body that can prevent contamination of the sea.The present invention relates to an internal reinforcing body forming step of forming an internal reinforcing body having a space by using any one of polyethylene, polypropylene, polyvinyl chloride and FRP A side finishing welding step of welding through both ends of the inner reinforcing body through a finishing weld A mesh weaving step of weaving a mesh comprising weft and warp obtained by extrusion The mesh sheet in which the mesh is located at the center is composed of 10 to 30 parts by weight of mPE-2, 60 to 100 parts by weight of low-density polyethylene, 1 to 3 parts by weight of UV stabilizer, 1 to 3 parts by weight of UV-By weight of a pigment, and 1 to 5 parts by weight of a pigment is extruded to have a predetermined thickness in an extruder Feeding the mesh sheet to a stretching machine and stretching the stretched mesh sheet in a transverse direction and a longitudinal direction in a range of 10 to 40% while heating at 110 to 135C A side coating step of cutting a circular finishing sheet with a circular or square shape to coat the outer side of the side finishing plate, applying an adhesive to one side, and pressing the side finishing plate against the side finishing plate The mesh sheet is joined to the outer diameter of the inner reinforcing body and the in
