An optical waveguide device which is free from interference with an optical path between a light emitting element and an optical waveguide thereof, and to provide a method of manufacturing the optical waveguide device. A light emitting element (5) is provided on an upper surface of a first under-cladding layer (21), and a second under-cladding layer (22) is provided on the upper surface of the first under-cladding layer (21), covering the light emitting element (5). A core 3 which receives light emitted from the light emitting element (5) through the second under-cladding layer (22) is provided on an upper surface of the second under-cladding layer (22). The core (3) is located in a position such that the light emitted from the light emitting element (5) is incident on the core (3).