A method for manufacturing a catheter includes preparing raw materials and maturing the raw materials in a drier at 50-55° C. for 20 days, preparing the expandable member, and the first and second tubes, in forms, by cutting the raw materials, fitting an index ring on the second tube, welding the expandable member to the first tube, and welding the expandable member with the second tube, connecting the first tube to a first side of the manifold, and connecting the second tube to a second side of the manifold, forming a shape and a size of the expandable member, and drying an interior of the expandable member and the second tube and maturing the expandable member for 24 hours in the drier at 50-55° C., then for 48 hours in the drier at 50-55° C.