A lens device is provided and includes: at least two lenses; and a lens frame holding the at least two lenses. The lens frame includes a first lens frame holding one of the at least two lenses and a second lens frame holding another of the at least two lenses, and the first lens frame and the second lens frame are attached in a line contact in circumferential directions thereof. The first lens frame and the second lens frame are bonded after an optical adjustment of the at least two lenses by relatively swinging the first lens framed and the second lens frame with respect to the line contact.