A hair cutting device of the present disclosure comprises an optical waveguide and a holding member that holds the optical waveguide. The optical waveguide comprises a light irradiator. The light irradiator irradiates hair protruding from skin with light to cut the hair. The holding member holds the optical waveguide in such a way that the light irradiator is exposed from at least one surface. As a result, even when the hair or the skin comes in contact with the light irradiator, misalignment or the like of the optical waveguide hardly occurs. This results in the improved hair cutting device being provided.