The miniaturization and energy efficient method have been demanded for a gimbal device equipped with optical instrument. So the gimbal structures, equippable with a camera and a lens, are compared for investigation. Results of these investigation, the remarkable improvement was not confirmed to gimbal structures such as AZ / EL, X-Y, and Slant-axis Joint. Therefore the structure applied with a Slant-axis Joint and a fiberscope was considered and proposed, and improvement of the gimbal device equipped with optical instrument was implemented.