There is provided a method of manufacturing an optical waveguide, the method including: allowing a beam to be incident in an optical waveguide direction of an optical waveguide material; generating an optical soliton in the optical waveguide material by adjusting intensity of the incident beam according to the optical waveguide material; allowing the incident beam to be re-incident at an intensity higher than an intensity of the incident beam after checking generation of the optical soliton in the optical waveguide material; and increasing a refractive index of an optical soliton-generating area of the optical waveguide material by the re-incident beam to thereby form an optical waveguide.